presentation layer info

Engineering Mathematics
Discrete Mathematics
Operating System
Computer Networks
Digital Logic and Design
C Programming
Data Structures
Theory of Computation
Compiler Design
Computer Org and Architecture

Presentation Layer in OSI model

Prerequisite : OSI Model

Introduction : Presentation Layer is the 6th layer in the Open System Interconnection (OSI) model. This layer is also known as Translation layer, as this layer serves as a data translator for the network. The data which this layer receives from the Application Layer is extracted and manipulated here as per the required format to transmit over the network. The main responsibility of this layer is to provide or define the data format and encryption. The presentation layer is also called as Syntax layer since it is responsible for maintaining the proper syntax of the data which it either receives or transmits to other layer(s).

Functions of Presentation Layer :

The presentation layer, being the 6th layer in the OSI model, performs several types of functions, which are described below-

Presentation layer format and encrypts data to be sent across the network.
This layer takes care that the data is sent in such a way that the receiver will understand the information (data) and will be able to use the data efficiently and effectively.
This layer manages the abstract data structures and allows high-level data structures (example- banking records), which are to be defined or exchanged.
This layer carries out the encryption at the transmitter and decryption at the receiver.
This layer carries out data compression to reduce the bandwidth of the data to be transmitted (the primary goal of data compression is to reduce the number of bits which is to be transmitted).
This layer is responsible for interoperability (ability of computers to exchange and make use of information) between encoding methods as different computers use different encoding methods.
This layer basically deals with the presentation part of the data.
Presentation layer, carries out the data compression (number of bits reduction while transmission), which in return improves the data throughput.
This layer also deals with the issues of string representation.
The presentation layer is also responsible for integrating all the formats into a standardized format for efficient and effective communication.
This layer encodes the message from the user-dependent format to the common format and vice-versa for communication between dissimilar systems.
This layer deals with the syntax and semantics of the messages.
This layer also ensures that the messages which are to be presented to the upper as well as the lower layer should be standardized as well as in an accurate format too.
Presentation layer is also responsible for translation, formatting, and delivery of information for processing or display.
This layer also performs serialization (process of translating a data structure or an object into a format that can be stored or transmitted easily).

Features of Presentation Layer in the OSI model: Presentation layer, being the 6th layer in the OSI model, plays a vital role while communication is taking place between two devices in a network.

List of features which are provided by the presentation layer are:

Presentation layer could apply certain sophisticated compression techniques, so fewer bytes of data are required to represent the information when it is sent over the network.
If two or more devices are communicating over an encrypted connection, then this presentation layer is responsible for adding encryption on the sender’s end as well as the decoding the encryption on the receiver’s end so that it can represent the application layer with unencrypted, readable data.
This layer formats and encrypts data to be sent over a network, providing freedom from compatibility problems.
This presentation layer also negotiates the Transfer Syntax.
This presentation layer is also responsible for compressing data it receives from the application layer before delivering it to the session layer (which is the 5th layer in the OSI model) and thus improves the speed as well as the efficiency of communication by minimizing the amount of the data to be transferred.

Working of Presentation Layer in the OSI model : Presentation layer in the OSI model, as a translator, converts the data sent by the application layer of the transmitting node into an acceptable and compatible data format based on the applicable network protocol and architecture. Upon arrival at the receiving computer, the presentation layer translates data into an acceptable format usable by the application layer. Basically, in other words, this layer takes care of any issues occurring when transmitted data must be viewed in a format different from the original format. Being the functional part of the OSI mode, the presentation layer performs a multitude (large number of) data conversion algorithms and character translation functions. Mainly, this layer is responsible for managing two network characteristics: protocol (set of rules) and architecture.

Presentation Layer Protocols : Presentation layer being the 6th layer, but the most important layer in the OSI model performs several types of functionalities, which makes sure that data which is being transferred or received should be accurate or clear to all the devices which are there in a closed network. Presentation Layer, for performing translations or other specified functions, needs to use certain protocols which are defined below –

Apple Filing Protocol (AFP): Apple Filing Protocol is the proprietary network protocol (communications protocol) that offers services to macOS or the classic macOS. This is basically the network file control protocol specifically designed for Mac-based platforms.
Lightweight Presentation Protocol (LPP): Lightweight Presentation Protocol is that protocol which is used to provide ISO presentation services on the top of TCP/IP based protocol stacks.
NetWare Core Protocol (NCP): NetWare Core Protocol is the network protocol which is used to access file, print, directory, clock synchronization, messaging, remote command execution and other network service functions.
Network Data Representation (NDR): Network Data Representation is basically the implementation of the presentation layer in the OSI model, which provides or defines various primitive data types, constructed data types and also several types of data representations.
External Data Representation (XDR): External Data Representation (XDR) is the standard for the description and encoding of data. It is useful for transferring data between computer architectures and has been used to communicate data between very diverse machines. Converting from local representation to XDR is called encoding, whereas converting XDR into local representation is called decoding.
Secure Socket Layer (SSL): The Secure Socket Layer protocol provides security to the data that is being transferred between the web browser and the server. SSL encrypts the link between a web server and a browser, which ensures that all data passed between them remains private and free from attacks.

Please Login to comment...

Improve your Coding Skills with Practice

What kind of Experience do you want to share?

Layer 6 Presentation Layer

De/Encryption, Encoding, String representation

The presentation layer (data presentation layer, data provision level) sets the system-dependent representation of the data (for example, ASCII, EBCDIC) into an independent form, enabling the syntactically correct data exchange between different systems. Also, functions such as data compression and encryption are guaranteed that data to be sent by the application layer of a system that can be read by the application layer of another system to the layer 6. The presentation layer. If necessary, the presentation layer acts as a translator between different data formats, by making an understandable for both systems data format, the ASN.1 (Abstract Syntax Notation One) used.

OSI Layer 6 - Presentation Layer

The presentation layer is responsible for the delivery and formatting of information to the application layer for further processing or display. It relieves the application layer of concern regarding syntactical differences in data representation within the end-user systems. An example of a presentation service would be the conversion of an EBCDIC-coded text computer file to an ASCII-coded file. The presentation layer is the lowest layer at which application programmers consider data structure and presentation, instead of simply sending data in the form of datagrams or packets between hosts. This layer deals with issues of string representation - whether they use the Pascal method (an integer length field followed by the specified amount of bytes) or the C/C++ method (null-terminated strings, e.g. "thisisastring\0"). The idea is that the application layer should be able to point at the data to be moved, and the presentation layer will deal with the rest. Serialization of complex data structures into flat byte-strings (using mechanisms such as TLV or XML) can be thought of as the key functionality of the presentation layer. Encryption is typically done at this level too, although it can be done on the application, session, transport, or network layers, each having its own advantages and disadvantages. Decryption is also handled at the presentation layer. For example, when logging on to bank account sites the presentation layer will decrypt the data as it is received.[1] Another example is representing structure, which is normally standardized at this level, often by using XML. As well as simple pieces of data, like strings, more complicated things are standardized in this layer. Two common examples are 'objects' in object-oriented programming, and the exact way that streaming video is transmitted. In many widely used applications and protocols, no distinction is made between the presentation and application layers. For example, HyperText Transfer Protocol (HTTP), generally regarded as an application-layer protocol, has presentation-layer aspects such as the ability to identify character encoding for proper conversion, which is then done in the application layer. Within the service layering semantics of the OSI network architecture, the presentation layer responds to service requests from the application layer and issues service requests to the session layer. In the OSI model: the presentation layer ensures the information that the application layer of one system sends out is readable by the application layer of another system. For example, a PC program communicates with another computer, one using extended binary coded decimal interchange code (EBCDIC) and the other using ASCII to represent the same characters. If necessary, the presentation layer might be able to translate between multiple data formats by using a common format. Wikipedia

Data conversion
Character code translation
Compression
Encryption and Decryption

The Presentation OSI Layer is usually composed of 2 sublayers that are:

CASE common application service element

ACSE	Association Control Service Element
ROSE	Remote Operation Service Element
CCR	Commitment Concurrency and Recovery
RTSE	Reliable Transfer Service Element

SASE specific application service element

FTAM	File Transfer, Access and Manager
VT	Virtual Terminal
MOTIS	Message Oriented Text Interchange Standard
CMIP	Common Management Information Protocol
JTM	Job Transfer and Manipulation
MMS	Manufacturing Messaging Service
RDA	Remote Database Access
DTP	Distributed Transaction Processing

Layer 7 Application Layer

Layer 6 presentation layer, layer 5 session layer, layer 4 transport layer, layer 3 network layer, layer 2 data link layer, layer 1 physical layer.

The OSI Model – The 7 Layers of Networking Explained in Plain English

This article explains the Open Systems Interconnection (OSI) model and the 7 layers of networking, in plain English.

The OSI model is a conceptual framework that is used to describe how a network functions. In plain English, the OSI model helped standardize the way computer systems send information to each other.

Learning networking is a bit like learning a language - there are lots of standards and then some exceptions. Therefore, it’s important to really understand that the OSI model is not a set of rules. It is a tool for understanding how networks function.

Once you learn the OSI model, you will be able to further understand and appreciate this glorious entity we call the Internet, as well as be able to troubleshoot networking issues with greater fluency and ease.

All hail the Internet!

Prerequisites

You don’t need any prior programming or networking experience to understand this article. However, you will need:

Basic familiarity with common networking terms (explained below)
A curiosity about how things work :)

Learning Objectives

Over the course of this article, you will learn:

What the OSI model is
The purpose of each of the 7 layers
The problems that can happen at each of the 7 layers
The difference between TCP/IP model and the OSI model

Common Networking Terms

Here are some common networking terms that you should be familiar with to get the most out of this article. I’ll use these terms when I talk about OSI layers next.

A node is a physical electronic device hooked up to a network, for example a computer, printer, router, and so on. If set up properly, a node is capable of sending and/or receiving information over a network.

Nodes may be set up adjacent to one other, wherein Node A can connect directly to Node B, or there may be an intermediate node, like a switch or a router, set up between Node A and Node B.

Typically, routers connect networks to the Internet and switches operate within a network to facilitate intra-network communication. Learn more about hub vs. switch vs. router.

Here's an example:

For the nitpicky among us (yep, I see you), host is another term that you will encounter in networking. I will define a host as a type of node that requires an IP address. All hosts are nodes, but not all nodes are hosts. Please Tweet angrily at me if you disagree.

Links connect nodes on a network. Links can be wired, like Ethernet, or cable-free, like WiFi.

Links to can either be point-to-point, where Node A is connected to Node B, or multipoint, where Node A is connected to Node B and Node C.

When we’re talking about information being transmitted, this may also be described as a one-to-one vs. a one-to-many relationship.

A protocol is a mutually agreed upon set of rules that allows two nodes on a network to exchange data.

“A protocol defines the rules governing the syntax (what can be communicated), semantics (how it can be communicated), and synchronization (when and at what speed it can be communicated) of the communications procedure. Protocols can be implemented on hardware, software, or a combination of both. Protocols can be created by anyone, but the most widely adopted protocols are based on standards.” - The Illustrated Network.

Both wired and cable-free links can have protocols.

While anyone can create a protocol, the most widely adopted protocols are often based on standards published by Internet organizations such as the Internet Engineering Task Force (IETF).

A network is a general term for a group of computers, printers, or any other device that wants to share data.

Network types include LAN, HAN, CAN, MAN, WAN, BAN, or VPN. Think I’m just randomly rhyming things with the word can ? I can ’t say I am - these are all real network types. Learn more here .

Topology describes how nodes and links fit together in a network configuration, often depicted in a diagram. Here are some common network topology types:

What is Network Topology? Best Guides to Types & Diagrams - DNSstuff

A network consists of nodes, links between nodes, and protocols that govern data transmission between nodes.

At whatever scale and complexity networks get to, you will understand what’s happening in all computer networks by learning the OSI model and 7 layers of networking.

What is the OSI Model?

The OSI model consists of 7 layers of networking.

First, what’s a layer?

No, a layer - not a lair . Here there are no dragons.

A layer is a way of categorizing and grouping functionality and behavior on and of a network.

In the OSI model, layers are organized from the most tangible and most physical, to less tangible and less physical but closer to the end user.

Each layer abstracts lower level functionality away until by the time you get to the highest layer. All the details and inner workings of all the other layers are hidden from the end user.

How to remember all the names of the layers? Easy.

Please | Physical Layer
Do | Data Link Layer
Not | Network Layer
Tell (the) | Transport Layer
Secret | Session Layer
Password (to) | Presentation Layer
Anyone | Application Layer

Keep in mind that while certain technologies, like protocols, may logically “belong to” one layer more than another, not all technologies fit neatly into a single layer in the OSI model. For example, Ethernet, 802.11 (Wifi) and the Address Resolution Protocol (ARP) procedure operate on >1 layer.

The OSI is a model and a tool, not a set of rules.

OSI Layer 1

Layer 1 is the physical layer . There’s a lot of technology in Layer 1 - everything from physical network devices, cabling, to how the cables hook up to the devices. Plus if we don’t need cables, what the signal type and transmission methods are (for example, wireless broadband).

Instead of listing every type of technology in Layer 1, I’ve created broader categories for these technologies. I encourage readers to learn more about each of these categories:

Nodes (devices) and networking hardware components. Devices include hubs, repeaters, routers, computers, printers, and so on. Hardware components that live inside of these devices include antennas, amplifiers, Network Interface Cards (NICs), and more.
Device interface mechanics. How and where does a cable connect to a device (cable connector and device socket)? What is the size and shape of the connector, and how many pins does it have? What dictates when a pin is active or inactive?
Functional and procedural logic. What is the function of each pin in the connector - send or receive? What procedural logic dictates the sequence of events so a node can start to communicate with another node on Layer 2?
Cabling protocols and specifications. Ethernet (CAT), USB, Digital Subscriber Line (DSL) , and more. Specifications include maximum cable length, modulation techniques, radio specifications, line coding, and bits synchronization (more on that below).
Cable types. Options include shielded or unshielded twisted pair, untwisted pair, coaxial and so on. Learn more about cable types here .
Signal type. Baseband is a single bit stream at a time, like a railway track - one-way only. Broadband consists of multiple bit streams at the same time, like a bi-directional highway.
Signal transmission method (may be wired or cable-free). Options include electrical (Ethernet), light (optical networks, fiber optics), radio waves (802.11 WiFi, a/b/g/n/ac/ax variants or Bluetooth). If cable-free, then also consider frequency: 2.5 GHz vs. 5 GHz. If it’s cabled, consider voltage. If cabled and Ethernet, also consider networking standards like 100BASE-T and related standards.

The data unit on Layer 1 is the bit.

A bit the smallest unit of transmittable digital information. Bits are binary, so either a 0 or a 1. Bytes, consisting of 8 bits, are used to represent single characters, like a letter, numeral, or symbol.

Bits are sent to and from hardware devices in accordance with the supported data rate (transmission rate, in number of bits per second or millisecond) and are synchronized so the number of bits sent and received per unit of time remains consistent (this is called bit synchronization). The way bits are transmitted depends on the signal transmission method.

Nodes can send, receive, or send and receive bits. If they can only do one, then the node uses a simplex mode. If they can do both, then the node uses a duplex mode. If a node can send and receive at the same time, it’s full-duplex – if not, it’s just half-duplex.

The original Ethernet was half-duplex. Full-duplex Ethernet is an option now, given the right equipment.

How to Troubleshoot OSI Layer 1 Problems

Here are some Layer 1 problems to watch out for:

Defunct cables, for example damaged wires or broken connectors
Broken hardware network devices, for example damaged circuits
Stuff being unplugged (...we’ve all been there)

If there are issues in Layer 1, anything beyond Layer 1 will not function properly.

Layer 1 contains the infrastructure that makes communication on networks possible.

It defines the electrical, mechanical, procedural, and functional specifications for activating, maintaining, and deactivating physical links between network devices. - Source

Fun fact: deep-sea communications cables transmit data around the world. This map will blow your mind: https://www.submarinecablemap.com/

And because you made it this far, here’s a koala:

OSI Layer 2

Layer 2 is the data link layer . Layer 2 defines how data is formatted for transmission, how much data can flow between nodes, for how long, and what to do when errors are detected in this flow.

In more official tech terms:

Line discipline. Who should talk for how long? How long should nodes be able to transit information for?
Flow control. How much data should be transmitted?
Error control - detection and correction . All data transmission methods have potential for errors, from electrical spikes to dirty connectors. Once Layer 2 technologies tell network administrators about an issue on Layer 2 or Layer 1, the system administrator can correct for those errors on subsequent layers. Layer 2 is mostly concerned with error detection, not error correction. ( Source )

There are two distinct sublayers within Layer 2:

Media Access Control (MAC): the MAC sublayer handles the assignment of a hardware identification number, called a MAC address, that uniquely identifies each device on a network. No two devices should have the same MAC address. The MAC address is assigned at the point of manufacturing. It is automatically recognized by most networks. MAC addresses live on Network Interface Cards (NICs). Switches keep track of all MAC addresses on a network. Learn more about MAC addresses on PC Mag and in this article . Learn more about network switches here .
Logical Link Control (LLC): the LLC sublayer handles framing addressing and flow control. The speed depends on the link between nodes, for example Ethernet or Wifi.

The data unit on Layer 2 is a frame .

Each frame contains a frame header, body, and a frame trailer:

Header: typically includes MAC addresses for the source and destination nodes.
Body: consists of the bits being transmitted.
Trailer: includes error detection information. When errors are detected, and depending on the implementation or configuration of a network or protocol, frames may be discarded or the error may be reported up to higher layers for further error correction. Examples of error detection mechanisms: Cyclic Redundancy Check (CRC) and Frame Check Sequence (FCS). Learn more about error detection techniques here .

Example of frames, the network layer, and the physical layer

Typically there is a maximum frame size limit, called an Maximum Transmission Unit, MTU. Jumbo frames exceed the standard MTU, learn more about jumbo frames here .

How to Troubleshoot OSI Layer 2 Problems

Here are some Layer 2 problems to watch out for:

All the problems that can occur on Layer 1
Unsuccessful connections (sessions) between two nodes
Sessions that are successfully established but intermittently fail
Frame collisions

The Data Link Layer allows nodes to communicate with each other within a local area network. The foundations of line discipline, flow control, and error control are established in this layer.

OSI Layer 3

Layer 3 is the network layer . This is where we send information between and across networks through the use of routers. Instead of just node-to-node communication, we can now do network-to-network communication.

Routers are the workhorse of Layer 3 - we couldn’t have Layer 3 without them. They move data packets across multiple networks.

Not only do they connect to Internet Service Providers (ISPs) to provide access to the Internet, they also keep track of what’s on its network (remember that switches keep track of all MAC addresses on a network), what other networks it’s connected to, and the different paths for routing data packets across these networks.

Routers store all of this addressing and routing information in routing tables.

Here’s a simple example of a routing table:

A routing table showing the destination, subnet mask, and interface

The data unit on Layer 3 is the data packet . Typically, each data packet contains a frame plus an IP address information wrapper. In other words, frames are encapsulated by Layer 3 addressing information.

The data being transmitted in a packet is also sometimes called the payload . While each packet has everything it needs to get to its destination, whether or not it makes it there is another story.

Layer 3 transmissions are connectionless, or best effort - they don't do anything but send the traffic where it’s supposed to go. More on data transport protocols on Layer 4.

Once a node is connected to the Internet, it is assigned an Internet Protocol (IP) address, which looks either like 172.16. 254.1 (IPv4 address convention) or like 2001:0db8:85a3:0000:0000:8a2e:0370:7334 (IPv6 address convention). Routers use IP addresses in their routing tables.

IP addresses are associated with the physical node’s MAC address via the Address Resolution Protocol (ARP), which resolves MAC addresses with the node’s corresponding IP address.

ARP is conventionally considered part of Layer 2, but since IP addresses don’t exist until Layer 3, it’s also part of Layer 3.

How to Troubleshoot OSI Layer 3 Problems

Here are some Layer 3 problems to watch out for:

All the problems that can crop up on previous layers :)
Faulty or non-functional router or other node
IP address is incorrectly configured

Many answers to Layer 3 questions will require the use of command-line tools like ping , trace , show ip route , or show ip protocols . Learn more about troubleshooting on layer 1-3 here .

The Network Layer allows nodes to connect to the Internet and send information across different networks.

OSI Layer 4

Layer 4 is the transport layer . This where we dive into the nitty gritty specifics of the connection between two nodes and how information is transmitted between them. It builds on the functions of Layer 2 - line discipline, flow control, and error control.

This layer is also responsible for data packet segmentation, or how data packets are broken up and sent over the network.

Unlike the previous layer, Layer 4 also has an understanding of the whole message, not just the contents of each individual data packet. With this understanding, Layer 4 is able to manage network congestion by not sending all the packets at once.

The data units of Layer 4 go by a few names. For TCP, the data unit is a packet. For UDP, a packet is referred to as a datagram. I’ll just use the term data packet here for the sake of simplicity.

Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are two of the most well-known protocols in Layer 4.

TCP, a connection-oriented protocol, prioritizes data quality over speed.

TCP explicitly establishes a connection with the destination node and requires a handshake between the source and destination nodes when data is transmitted. The handshake confirms that data was received. If the destination node does not receive all of the data, TCP will ask for a retry.

TCP also ensures that packets are delivered or reassembled in the correct order. Learn more about TCP here .

UDP, a connectionless protocol, prioritizes speed over data quality. UDP does not require a handshake, which is why it’s called connectionless.

Because UDP doesn’t have to wait for this acknowledgement, it can send data at a faster rate, but not all of the data may be successfully transmitted and we’d never know.

If information is split up into multiple datagrams, unless those datagrams contain a sequence number, UDP does not ensure that packets are reassembled in the correct order. Learn more about UDP here .

TCP and UDP both send data to specific ports on a network device, which has an IP address. The combination of the IP address and the port number is called a socket.

Learn more about sockets here .

Learn more about the differences and similarities between these two protocols here .

How to Troubleshoot OSI Layer 4 Problems

Here are some Layer 4 problems to watch out for:

Blocked ports - check your Access Control Lists (ACL) & firewalls
Quality of Service (QoS) settings. QoS is a feature of routers/switches that can prioritize traffic, and they can really muck things up. Learn more about QoS here .

The Transport Layer provides end-to-end transmission of a message by segmenting a message into multiple data packets; the layer supports connection-oriented and connectionless communication.

OSI Layer 5

Layer 5 is the session layer . This layer establishes, maintains, and terminates sessions.

A session is a mutually agreed upon connection that is established between two network applications. Not two nodes! Nope, we’ve moved on from nodes. They were so Layer 4.

Just kidding, we still have nodes, but Layer 5 doesn’t need to retain the concept of a node because that’s been abstracted out (taken care of) by previous layers.

So a session is a connection that is established between two specific end-user applications. There are two important concepts to consider here:

Client and server model: the application requesting the information is called the client, and the application that has the requested information is called the server.
Request and response model: while a session is being established and during a session, there is a constant back-and-forth of requests for information and responses containing that information or “hey, I don’t have what you’re requesting.”

Sessions may be open for a very short amount of time or a long amount of time. They may fail sometimes, too.

Depending on the protocol in question, various failure resolution processes may kick in. Depending on the applications/protocols/hardware in use, sessions may support simplex, half-duplex, or full-duplex modes.

Examples of protocols on Layer 5 include Network Basic Input Output System (NetBIOS) and Remote Procedure Call Protocol (RPC), and many others.

From here on out (layer 5 and up), networks are focused on ways of making connections to end-user applications and displaying data to the user.

How to Troubleshoot OSI Layer 5 Problems

Here are some Layer 5 problems to watch out for:

Servers are unavailable
Servers are incorrectly configured, for example Apache or PHP configs
Session failure - disconnect, timeout, and so on.

The Session Layer initiates, maintains, and terminates connections between two end-user applications. It responds to requests from the presentation layer and issues requests to the transport layer.

OSI Layer 6

Layer 6 is the presentation layer . This layer is responsible for data formatting, such as character encoding and conversions, and data encryption.

The operating system that hosts the end-user application is typically involved in Layer 6 processes. This functionality is not always implemented in a network protocol.

Layer 6 makes sure that end-user applications operating on Layer 7 can successfully consume data and, of course, eventually display it.

There are three data formatting methods to be aware of:

American Standard Code for Information Interchange (ASCII): this 7-bit encoding technique is the most widely used standard for character encoding. One superset is ISO-8859-1, which provides most of the characters necessary for languages spoken in Western Europe.
Extended Binary-Coded Decimal Interchange Code (EBDCIC): designed by IBM for mainframe usage. This encoding is incompatible with other character encoding methods.
Unicode: character encodings can be done with 32-, 16-, or 8-bit characters and attempts to accommodate every known, written alphabet.

Learn more about character encoding methods in this article , and also here .

Encryption: SSL or TLS encryption protocols live on Layer 6. These encryption protocols help ensure that transmitted data is less vulnerable to malicious actors by providing authentication and data encryption for nodes operating on a network. TLS is the successor to SSL.

How to Troubleshoot OSI Layer 6 Problems

Here are some Layer 6 problems to watch out for:

Non-existent or corrupted drivers
Incorrect OS user access level

The Presentation Layer formats and encrypts data.

OSI Layer 7

Layer 7 is the application layer .

True to its name, this is the layer that is ultimately responsible for supporting services used by end-user applications. Applications include software programs that are installed on the operating system, like Internet browsers (for example, Firefox) or word processing programs (for example, Microsoft Word).

Applications can perform specialized network functions under the hood and require specialized services that fall under the umbrella of Layer 7.

Electronic mail programs, for example, are specifically created to run over a network and utilize networking functionality, such as email protocols, which fall under Layer 7.

Applications will also control end-user interaction, such as security checks (for example, MFA), identification of two participants, initiation of an exchange of information, and so on.

Protocols that operate on this level include File Transfer Protocol (FTP), Secure Shell (SSH), Simple Mail Transfer Protocol (SMTP), Internet Message Access Protocol (IMAP), Domain Name Service (DNS), and Hypertext Transfer Protocol (HTTP).

While each of these protocols serve different functions and operate differently, on a high level they all facilitate the communication of information. ( Source )

How to Troubleshoot OSI Layer 7 Problems

Here are some Layer 7 problems to watch out for:

All issues on previous layers
Incorrectly configured software applications
User error (... we’ve all been there)

The Application Layer owns the services and functions that end-user applications need to work. It does not include the applications themselves.

Our Layer 1 koala is all grown up.

Learning check - can you apply makeup to a koala?

Don’t have a koala?

Well - answer these questions instead. It’s the next best thing, I promise.

What is the OSI model?
What are each of the layers?
How could I use this information to troubleshoot networking issues?

Congratulations - you’ve taken one step farther to understanding the glorious entity we call the Internet.

Learning Resources

Many, very smart people have written entire books about the OSI model or entire books about specific layers. I encourage readers to check out any O’Reilly-published books about the subject or about network engineering in general.

Here are some resources I used when writing this article:

The Illustrated Network, 2nd Edition
Protocol Data Unit (PDU): https://www.geeksforgeeks.org/difference-between-segments-packets-and-frames/
Troubleshooting Along the OSI Model: https://www.pearsonitcertification.com/articles/article.aspx?p=1730891
The OSI Model Demystified: https://www.youtube.com/watch?v=HEEnLZV2wGI
OSI Model for Dummies: https://www.dummies.com/programming/networking/layers-in-the-osi-model-of-a-computer-network/

Chloe Tucker is an artist and computer science enthusiast based in Portland, Oregon. As a former educator, she's continuously searching for the intersection of learning and teaching, or technology and art. Reach out to her on Twitter @_chloetucker and check out her website at chloe.dev .

Presentation Layer

Last Edited

What is the Presentation Layer?

Presentation Layer is the Layer 6 of the seven-layer Open Systems Interconnection (OSI) reference model . The presentation layer structures data that is passed down from the application layer into a format suitable for network transmission. This layer is responsible for data encryption, data compression, character set conversion, interpretation of graphics commands, and so on. The network redirector also functions at this layer.

Presentation Layer functions

Translation: Before being transmitted, information in the form of characters and numbers should be changed to bit streams. Layer 6 is responsible for interoperability between encoding methods as different computers use different encoding methods. It translates data between the formats the network requires and the format the computer.
Encryption: Encryption at the transmitter and decryption at the receiver
Compression: Data compression to reduce the bandwidth of the data to be transmitted. The primary role of data compression is to reduce the number of bits to be transmitted. Multimedia files, such as audio and video, are bigger than text files and compression is more important.

Role of Presentation Layer in the OSI Model

This layer is not always used in network communications because its functions are not always necessary. Translation is only needed if different types of machines need to talk with each other. Encryption is optional in communication. If the information is public there is no need to encrypt and decrypt info. Compression is also optional. If files are small there is no need for compression.

Explaining Layer 6 in video

Most real-world protocol suites, such as TCP/IP , do not use separate presentation layer protocols. This layer is mostly an abstraction in real-world networking.

An example of a program that loosely adheres to layer 6 of OSI is the tool that manages the Hypertext Transfer Protocol (HTTP) — although it’s technically considered an application-layer protocol per the TCP/IP model.

However, HTTP includes presentation layer services within it. HTTP works when the requesting device forwards user requests passed to the web browser onto a web server elsewhere in the network.

It receives a return message from the web server that includes a multipurpose internet mail extensions (MIME) header. The MIME header indicates the type of file – text, video, or audio – that has been received so that an appropriate player utility can be used to present the file to the user.

In short, the presentation layer

Makes sure that data which is being transferred or received should be accurate or clear to all the devices which are there, in a closed network.

ensures proper formatting and delivery to and from the application layer;
performs data encryption; and
manages serialization of data objects.

Data Structure
Coding Problems
C Interview Programs
C++ Aptitude
Java Aptitude
C# Aptitude
PHP Aptitude
Linux Aptitude
DBMS Aptitude
Networking Aptitude
AI Aptitude
MIS Executive
Web Technologie MCQs
CS Subjects MCQs
Databases MCQs
Programming MCQs
Testing Software MCQs
Digital Mktg Subjects MCQs
Cloud Computing S/W MCQs
Engineering Subjects MCQs
Commerce MCQs
More MCQs...
Machine Learning/AI
Operating System
Computer Network
Software Engineering
Discrete Mathematics
Digital Electronics
Data Mining
Embedded Systems
Cryptography
CS Fundamental
More Tutorials...
Tech Articles
Code Examples
Programmer's Calculator
XML Sitemap Generator
Tools & Generators

Computer Network Tutorial

Computer Network - Home
Computer Network - Overview
Computer Network - Applications
Computer Network - TCP/IP
Computer Network - OSI Model
Computer Network - Transport, Network, & Application Layers
Computer Network - Network Protocols & Network Software
Computer Network - TopologiesTypes
Computer Network - Hub
Computer Network - Routing
Computer Network - Routers
Computer Network - Dynamic Routing Protocols
Computer Network - Router
Computer Network - Populating a Routing Table
Computer Network - Switches
Computer Network - Layer 2 Switching
Computer Network - Configure Cisco Switch
Computer Network - ICMP
Computer Network - ICMP Messages
Computer Network - Addressing
Computer Network - Classless Addressing
Computer Network - IPV4 Addressing
Computer Network - IPV6 Addressing
Computer Network - Logical Addressing, Notations
Computer Network - Classful & Classless Addressing
Computer Network - Subnetting & Supernetting
Computer Network - Network Address Translation
Computer Network - FLSM & VLSM
Computer Network - Line Configuration
Transmission Computer Network - Modes
Computer Network - Data Link Layer
Computer Network - Physical Layer
Computer Network - Network Layer
Computer Network - Session Layer
Computer Network - Transport Layer
Computer Network - Application Layer
Computer Network - Presentation Layer
Computer Network - Coaxial Cable
Computer Network - Optical Fiber
Computer Network - Unguided Transmission Media
Computer Network - Virtual LAN (VLAN)
Computer Network - VSAN
Computer Network - Multiple Access Protocol
Computer Network - Random Access methods
Computer Network - Aloha Network
Computer Network - CSMA
Computer Network - FDMA & TDMA
Computer Network - CDMA
Computer Network - Ethernet Technology
Computer Network - Types of Network Topology
Computer Network - Data Transmission
Computer Network - Switching Techniques
Computer Network - Transmission Impairment
Computer Network - Synchronous & Asynchronous Transmission
Computer Network - Intent-Based Networking
Computer Network - Software-Defined Networking
Computer Network - Wireless Personal Area Network
Computer Network - Wireless Wide Area Network
Computer Network - P2P File Sharing
Computer Network - Packet Switching
Computer Network - PGP - Authentication & Confidentiality
Computer Network - PGP - Encryption & Compression
Computer Network - Phishing Attacks
Computer Network - ICMP Ping
Computer Network - Pipelining in Packet Switching
Computer Network - Plaintext Vs. Cleartext Encryption
Computer Network - Platform as a Service (PaaS)
Computer Network - GPRS Architecture
Computer Network - Identify & Prevent Phishing & Pharming
Computer Network - Change MAC Address
Computer Network - Network Administrator Vs. Network Engineer

Difference B/W Articles

Computer Network - Phishing & Pharming
Computer Network - Ping Vs. Traceroute
Computer Network - Network Vs. System Administrator
Computer Network - Network & Application Layer Protocols
Computer Network - Network Security Vs. Network Administration
Computer Network - Network Vs. Internet
Computer Network - PDH Vs. SDH
Computer Network - PCI Vs. PCI express
Computer Network - PCI-E Vs. PCI-X
Computer Network - OT Vs. IT Networks

Computer Network Practice

Computer Network - MCQs
Computer Network - Aptitude Questions

Home » Computer Network

Presentation Layer: What It Is, Design Issues, Functionalities

Description and Functions of Presentation Layer in the OSI model: In this tutorial, we are going to learn what the Presentation layer is and the Functions of the Presentation Layer in the OSI model in Computer Networking. We will also discuss the Design issues with the Presentation Layer and the working of the Presentation Layer with the help of its diagram. By Monika Jha Last updated : May 05, 2023

What is Presentation Layer?

The Presentation Layer is concerned with the syntax and semantics of the information exchanged between two communicating devices.

The presentation layer takes care that the data is sent in that way the receiver of the data will understand the information (data) and will be able to use the data.
Languages that are syntax can be different from the two communicating machines. In this condition, the presentation layer plays the role of translator between them.
It is possible for two machines to communicate with different data representations, data structures to be exchanged can be defined in an abstract way.
These abstract data structures will be managed by the presentation layer and this layer allows higher-level data structures (For example banking records), to be defined and exchanged.

This figure shows the relationship of the presentation layer to the session layer and application layer.

Design Issues with Presentation Layer

The following are the design issues with presentation layer:

To manage and maintain the Syntax and Semantics of the information transmitted.
Encoding data in a standard agreed-upon way just like a string, double, date, etc.
It Performs Standard Encoding scheme on the wire.

Functionalities of the Presentation Layer

Specific functionalities of the presentation layer are as follows:

1. Translation

The processes or running programs in two machines are usually exchanging the information in the form of numbers, character strings and so on before being transmitted. The information should be changed to bitstreams because different computers use different encoding schemes.
The Presentation layer is responsible for compatibility between these encoding methods.
The Presentation layer at the sender's side changes the information from its sender dependent format.
The Presentation layer at the receiving machine changes the common format into its receivers dependent format.

Example: Convert ASCII code to EBCDIC code.

2. Encryption

The system must be able to assure privacy regarding the message or information as it also carries sensitive information.
Encryption means that the sender transforms the original information or message to another form, this data after encryption is known as the ciphertext and this ciphertext sends the resulting message out over the network.
Decryption concerned with the transform of the message back to its original form. This decrypted data is known as plain text.

3. Compression

Data Compression means reduces the number of bits to be transmitted by this reduce the bandwidth of the data.
Data Compression becomes particularly important in the transmission of multimedia such as audio, video, text, etc.

presentation layer

Andrew Froehlich, West Gate Networks

What is the presentation layer?

The presentation layer resides at Layer 6 of the Open Systems Interconnection ( OSI ) communications model and ensures that communications that pass through it are in the appropriate form for the recipient application. In other words, the presentation layer presents the data in a readable format from an application layer perspective.

For example, a presentation layer program could format a file transfer request in binary code to ensure a successful file transfer . Because binary is the most rudimentary of computing languages, it ensures that the receiving device can decipher and translate it into a format the application layer understands and expects.

How the presentation layer works

Once the application layer passes data meant for transport to another device in a certain format, the presentation layer then prepares this data in the most appropriate format the receiving application can understand.

Common data formats include the following:

American Standard Code for Information Interchange and Extended Binary Coded Decimal Interchange Code for text;
JPEG , GIF and TIFF for images; and
MPEG, MIDI and QuickTime for video.

Encryption and decryption of data communications are also performed at the presentation layer. Here, encryption methods and keys exchange between the two communicating devices. Only the sender and receiver can properly encode and decode data so it returns to a readable format.

The presentation layer can serialize -- or translate -- more complex application data objects into a storable and transportable format. This helps to rebuild the object once it arrives at the other side of the communications stream. The presentation layer also deserializes the data stream and places it back into an object format that the application can understand by the application.

Chart depicting the location of the presentation layer within the OSI model.

The tool that manages Hypertext Transfer Protocol ( HTTP ) is an example of a program that loosely adheres to the presentation layer of OSI.

Although it's technically considered an application-layer protocol per the TCP/IP model , HTTP includes presentation layer services within it. HTTP works when the requesting device forwards user requests passed to the web browser onto a web server elsewhere in the network.

HTTP receives a return message from the web server that includes a Multipurpose Internet Mail Extensions ( MIME ) header. The MIME header indicates the type of file -- text, video, or audio -- that has been received so that an appropriate player utility can present the file to the user.

Functions of the presentation layer

ensures proper formatting and delivery to and from the application layer;
performs data encryption; and
manages serialization of data objects.

Editor's note: This article was republished in January 2023 to improve the reader experience.

Continue Reading About presentation layer

What is the difference between TCP/IP model vs. OSI model?
Data and file formatting

Related Terms

Dig deeper on network infrastructure.

What are the most important email security protocols?

file extension (file format)

network protocol

MIME (Multipurpose Internet Mail Extensions)

Microsoft 365 Copilot, an AI assistant, offers several promising features. Find out how to configure Copilot with Teams workflows...

With its AI capabilities, Microsoft Copilot provides several enhancements to Microsoft Teams functionality, including meeting ...

Organizations have ramped up their use of communications platform as a service and APIs to expand communication channels between ...

To keep corporate and user data safe, IT must continuously ensure mobile app security. Mobile application security audits are a ...

Dell continues to cut its workforce to become 'leaner,' as it repositions for changes in the enterprise PC market that are ...

Tap to Pay makes it possible to accept customer payments from an iPhone with no additional hardware. Find out the best use cases ...

Due to rapid AI hardware advancement, companies are releasing advanced products yearly to keep up with the competition. The new ...

AMD plans to acquire AI systems designer and manufacturer ZT Systems for $5 billion. AMD CEO Lisa Su said hyperscalers want more ...

Data center modernization offers a competitive advantage to organizations, along with maximizing hyperscale infrastructure. ...

Popular pricing models for managed service providers include monitoring only, per device, per user, all-you-can-eat or ...

Global IT consultancies take a multilayered approach to GenAI training by developing in-house programs, partnering with tech ...

IT service providers are upskilling a large portion of their workforces on the emerging technology. The campaign seeks to boost ...

Physical Layer

Digital Transmission
Multiplexing
Circuit-Switched
Message-Switched Networks
Packet Switching

Transport layer

Transport Layer
Telnet vs SSH
UDP Protocol
TCP - Protocol

ISO/OSI REFERENCE MODEL

Introduction to Reference Models
OSI Model: Physical Layer
OSI Model: Datalink Layer
OSI Model: Network Layer
OSI Model: Transport Layer
OSI Model: Session Layer
OSI Model: Presentation Layer
OSI Model: Application Layer

TCP/IP REFERENCE MODELCOMPUTER NETWORKS

The TCP/IP Reference Model
Difference between OSI and TCP/IP Model
Key Terms - Computer Network

Session layer

Session Layer

Computer Networks

Components of Computer Networks
Features of Computer Network
Protocols and Standards
Connection Oriented and Connectionless
OSI Vs TCP/IP

Presentation layer

Presentation Layer

Application layer

HTTP Protocol
FTP Protocol
SMTP Protocol
POP Protocol
SNMP Protocol
Electronic Mail
MIME Protocol
World Wide Web
DNS Protocol

Presentation Layer - OSI Model

The primary goal of this layer is to take care of the syntax and semantics of the information exchanged between two communicating systems. Presentation layer takes care that the data is sent in such a way that the receiver will understand the information(data) and will be able to use the data. Languages(syntax) can be different of the two communicating systems. Under this condition presentation layer plays a role translator.

In order to make it possible for computers with different data representations to communicate, the data structures to be exchanged can be defined in an abstract way. The presentation layer manages these abstract data structures and allows higher-level data structures(eg: banking records), to be defined and exchanged.

Functions of Presentation Layer

Translation: Before being transmitted, information in the form of characters and numbers should be changed to bit streams. The presentation layer is responsible for interoperability between encoding methods as different computers use different encoding methods. It translates data between the formats the network requires and the format the computer.
Encryption: It carries out encryption at the transmitter and decryption at the receiver.
Compression: It carries out data compression to reduce the bandwidth of the data to be transmitted. The primary role of Data compression is to reduce the number of bits to be 0transmitted. It is important in transmitting multimedia such as audio, video, text etc.

Design Issues with Presentation Layer

To manage and maintain the Syntax and Semantics of the information transmitted.
Encoding data in a standard agreed upon way. Eg: String, double, date, etc.
Perform Standard Encoding on wire.
← Prev
Next →

CN MCQ Tests

gate interview tests.

What is Presentation Layer in the OSI Model?

InfosecTrain

The OSI model provides a standardized framework for the interaction and communication between various networking protocols and technologies within a network. It breaks down the communication process into seven distinct layers, each with specific responsibilities, and ensures that data communication between devices is seamless and uniform. One significant layer in the OSI model is the Presentation Layer.

Introduction to the Presentation Layer

The Presentation Layer, situated at Layer 6 of the OSI model, acts as an intermediary between the Application Layer (Layer 7) and the Session Layer (Layer 5). Its primary function is to ensure that the data exchanged between communicating systems is presented in a format that both the sender and the receiver can understand. This layer is responsible for data presentation, encryption, and compression, making it crucial for secure and efficient data transmission. It handles data formatting, converting the information from the application layer into a standardized format that can be easily transmitted over the network.

Presentation Layer Functions

Key functions of the Presentation Layer in the OSI model include:

Data Encryption: It securely encrypts data to prevent unauthorized access during transmission.
Data Compression: It reduces data size to enhance transmission efficiency and bandwidth usage.
Data Translation: It translates data across various character sets, data structures, and formats for compatibility.
Data Syntax Conversion: It ensures proper data encoding or decoding for uniform interpretation.
Graphics and Multimedia Handling: It handles the representation and conversion of multimedia data for transmission.
Data Integrity Checks: It implements error detection and correction mechanisms to maintain data accuracy.
Protocol Conversion: It enables seamless data exchange between communicating devices by adapting protocols.
Data Tokenization: It divides data into smaller segments to ensure efficient transmission and reassembly.
Data Encryption Key Management: It manages encryption keys to ensure secure device communication.
Compression Algorithms: It uses compression algorithms like JPEG and MPEG to optimize multimedia data transmission.

Protocols at the Presentation Layer

Below are some Presentation Layer protocols in the OSI model include:

ICA (Independent Computing Architecture): Enables efficient remote computing between client and server.
AFP (AppleTalk Filing Protocol): Allows users to access and share files and directories across an AppleTalk network.
PAD (Packet Assembler/Disassembler): Breaks data into packets and reassembles them during transmission.
XDR (eXternal Data Representation): Enables data exchange between systems with different architectures and data formats.
NCP (NetWare Core Protocol): Manages file, print, and directory services in Novell NetWare networks.
NDR (Network Data Representation): Ensures data format consistency across different systems.

Final Words

The Presentation Layer enables seamless communication among various applications and systems by managing data translation, encryption, and compression.

InfosecTrain ’s Network Security and CompTIA Network+ training courses cover various networking aspects, including the OSI model. We provide an in-depth understanding of the OSI model, emphasizing each layer’s functions, protocols, and significance, including the Presentation Layer. Our training course involves practical labs and exercises to provide participants with hands-on experience and insights into data representation, encryption, and compression techniques used in the Presentation Layer.

Written by InfosecTrain

https://www.infosectrain.com/courses/advanced-penetration-testing-online-training-course/

Text to speech

Presentation Layer In OSI Model : A Comprehensive Guide

In the vast landscape of computer networks, the OSI (Open Systems Interconnection) model stands as a fundamental framework for understanding how data is transmitted from one device to another. Among its seven layers, the presentation layer holds an important place, acting as a translator and formatter to ensure seamless communication between different systems. Through this article, we will try to know what is presentation layer in OSI model, what is its role in the field of networking and what is its importance.

Table of Contents

What is the Presentation Layer?

The Presentation Layer, within the OSI (Open Systems Interconnection) model, is the sixth layer. It focuses on the representation of data, ensuring that information exchanged between applications is formatted appropriately for transmission and receipt across a network. This layer handles tasks such as data translation, encryption, compression, and formatting. Its primary function is to ensure that data remains readable and understandable by both the sender and receiver, regardless of differences in data formats. In essence, the Presentation Layer acts as a translator and formatter, facilitating seamless communication between different systems and enhancing the reliability and security of data transmission.

Working of Presentation Layer

The Presentation Layer acts like a language translator and document formatter in the OSI model. It takes data from applications and prepares it for transmission over the network by translating it into a language that both the sender and receiver understand. Think of it as converting a letter into a universal format before mailing it overseas. Additionally, the Presentation Layer ensures that the data looks right by formatting it properly, like adjusting the font and spacing in a document. It also adds extra security by encrypting the data if needed, making it like a secret code that only the intended recipient can understand. Lastly, it might shrink the data down to save space during transmission, similar to compressing a file before emailing it. In short, the Presentation Layer makes sure data is ready for its journey across the network, keeping it secure, readable, and efficient along the way.

Functions of the Presentation Layer

Data Translation : Converting data from the format used by the application into a format suitable for transmission over the network, and vice versa, ensuring interoperability between different systems.
Encryption and Decryption : Securing data during transmission by encrypting it before sending and decrypting it upon reception, ensuring confidentiality and integrity of the information.
Data Compression : Reducing the size of data before transmission to optimize bandwidth usage and speed up the transfer process, improving network efficiency.
Data Formatting: Formatting data according to predefined standards for transmission, including character encoding, data structure, and multimedia representation, ensuring compatibility between sender and receiver applications.
Protocol Conversion : Adapting data between different network protocols or data formats, facilitating communication between systems with varying requirements or standards.
Character Code Translation: Converting characters between different character sets or encoding schemes to ensure proper interpretation of text-based data across systems with different language or encoding preferences.

Protocols are Use in Presentation layer

The Presentation Layer primarily focuses on data representation and formatting rather than specific protocols. However, some protocols or standards are commonly associated with the Presentation Layer due to their role in data representation and formatting. Here are a few examples.

MIME : MIME stands for Multipurpose Internet Mail Extensions. It’s a protocol that broadens the scope of email messages, enabling the use of text in various character sets beyond ASCII. Additionally, MIME facilitates the inclusion of attachments such as audio, video, images, and application programs within emails.
SSL/TLS : SSL/TLS protocols provide secure communication over a computer network by encrypting data between the client and server, ensuring data confidentiality and integrity. While SSL/TLS operate at the Transport Layer, they often involve encryption and decryption processes associated with the Presentation Layer.
ASCII (: ASCII and Unicode are character encoding standards that represent text characters using numerical codes. These standards ensure consistent representation of text characters across different systems and platforms, which is crucial for data interchange.
JPEG, GIF, PNG : These image file formats are commonly used for encoding and transmitting images over networks. While the specifics of image compression and encoding are often handled by the Application Layer, the Presentation Layer ensures proper interpretation and formatting of these image data.
PDF : PDF is a file format used to present and exchange documents reliably, independent of software, hardware, or operating systems. The Presentation Layer ensures proper interpretation and rendering of PDF documents for display or printing

the Presentation Layer of the OSI Model acts as a translator and formatter, ensuring that data exchanged between applications remains readable and compatible across diverse systems. By handling tasks such as data translation, encryption, compression, and formatting, it enhances the reliability, efficiency, and security of data transmission over networks. Essentially, the Presentation Layer plays a crucial role in facilitating seamless communication between different systems, ensuring that information is accurately represented and securely transmitted, thus contributing to the smooth functioning of modern networking environments.

Please Share This Share this content

Opens in a new window X
Opens in a new window Facebook
Opens in a new window Pinterest
Opens in a new window LinkedIn
Opens in a new window WhatsApp

Wifi full-form how it is important for our life, all about networking devices, router in computer network features, types & working.

Network Fundamentals
Network Cabling
Ethernet Protocol
TCP-UDP Protocol
IP Protocol
Supernetting & CIDR
ICMP Protocol
Domain Name System (DNS)
Spanning Tree Protocol (STP)
VLAN Networks
Network Address Translation
Cisco Routers
Cisco Switches
Cisco Firewalls
Cisco Wireless
Cisco CallManager-CCME
Cisco Data Center (Nexus/UCS)
Cisco Services & Technologies
Palo Alto Networks
F5 Networks
Microsoft 365 Security
SASE & SD-WAN
Security Service Edge (SSE)
Web Application Vulnerability Scanners
VPN Services & Guides
Windows Servers
Windows Workstations (XP, 7, 8, 10, 11)
Linux - Unix
Virtualization & VM Backup
OpManager - Network Monitoring & Management
ManageEngine Firewall Analyzer

EventLog Analyzer

Network Protocol Analyzers
IP PBX - Unified Communications
Security Articles
Reviews & Interviews
GFI Network Security
OpenMosix - Linux Supercomputer
More Reading

All-in-one protection

Free Download

Ransomware protection.

Download Now!

Free Download!

Get 2 vms for free.

Manage your Network!

The OSI Model: Layer 6 - Presentation Layer

The Presentation Layer gets its name from its purpose: It presents data to the Application layer. It's basically a translator and provides coding and conversion functions. A successful data transfer technique is to adapt the data into a standard format before transmission. Computers are configured to receive this generically formatted data and then convert the data back into its native format for reading. By providing translation services, the Presentation layer ensures that data transferred from the Application layer of one system can be read by the Application layer of another host.

JPEG: The Joint Photographic Experts Group brings these photo standards to us.

MIDI: The Musical Intrument Digital Interface is used for digitized music.

MPEG: The Moving Pictures Experts Group's standard for the compression and coding of motion video for CD's is very popular.

QuickTime: This is for use with Machintosh or Power PC programs, it manages audio and video applications.

The last 3 layers of the OSI model are reffered to the "Upper" layers. These layers are responsible for applications communicating between hosts. None of the upper layers know anything about networking or network addresses.

There are no protocols which work specificly at the Presentation layer, but the protocols which work at the Application layer are said to work on all 3 upper layers.

Next: The OSI Model: Layer 7 - Application Layer

Your IP address:

91.193.111.216

All-in-one protection for Microsoft 365

FREE Hyper-V & VMware Backup

Wi-Fi Key Generator

Network and server monitoring.

Follow Firewall.cx

Please enable the javascript to submit this form

Recommended Downloads

Network Management - Monitor & Alert
Free Hyper-V & VMware Backup

Bandwidth Monitor

Patch Manager Plus

Firewall Analyzer

Cisco password crack.

Decrypt Cisco Type-7 Passwords on the fly!

Decrypt Now!

Free PatchManager

Security Podcast

The osi model: layer 7 - application layer, the osi model: layer 2 - datalink layer, the osi model: layer 4 - transport layer, data encapsulation & decapsulation in the osi model, the osi model: layer 3 - network layer.

+971 (5) 281 10952
info@networkwalks.com
Cisco & IT Courses
Cyber Security & Hacking Courses
Premium Membership

Presentation Layer of OSI Model (Layer-6)

Presentation Layer is responsible for representation & formatting of data for session Layer in encapsulation process. It is the 6th Layer in the seven layer OSI Model after Session Layer. Presentation layer serves like a translator & takes care that the data is sent in such a way that the receiver will understand the information or data and will be able to use the data. OSI Model divides the network communication processes into seven layers in order to simplify it. Each layer performs specific functions to support the layers above it. This seven Layer model starts from Physical till Application Layer & Presentation Layer is on 2nd place in this model as in below figure:

Functions/Duties of Presentation Layer

Each Layer in OSI Model Performs some important duties. Important functions performed by Presentation Layer are listed here:

The first & most important is, of course Data Formatting & Representation . When the presentation layer receives data from the application layer, to be sent over the network, it makes sure that the data is in the proper format. If it is not, the presentation layer converts the data to the proper format. On the other side of communication, when the presentation layer receives network data from the Presentation layer, it makes sure that the data is in the proper format and once again converts it if it is not.
It is also responsible for Data Encryption/Decryption: Presentation Layer carries out encryption at the transmitter end and decryption at the receiver end to keep data secure during transmission.
Data Compression/De-compression also falls under the responsibility matrix of Presentation Layer . Presentation Layer compresses data to a small size to reduce resource usage such as data storage space or transmission capacity.

*Encryption is typically done at this layer as well, although it can be done on the application, session, transport, or network layers, each having its own advantages and disadvantages

Presentation Layer Protocols

The OSI Model provides a conceptual framework for communication between computers, but the model itself is not a method of communication. Actual communication is made possible by using communication protocols. Each layer on the OSI Model has some protocols associated with it. Some important protocols on Presentation layer are listed in below:

JPEG/GIF/PNG/TIFF

Network Equipment/Components at Presentation Layer

Load Balancers
End Devices e.g. Computers, Smart Phones, Servers, …

Presentation Layer is the 6th Layer in seven Layer OSI Model. It performs important functions like Data Formatting, Data Representation, Data Encryption/Decryption, Data Compression and De-compression. Important Protocols at Presentation Layer include ASCII, EBCDIC, JPEG, MPEG, GIF, PNG, TIFF, SSL & TLS. Equipment operating at Presentation Layer include Firewalls, Gateways, Load Balancers & Computers.

Now, test your knowledge on OSI Model using our free Quizzes & Cheat sheet resources for long term memory:

Networkwalks Summary Cheatsheets

Free Online Quizzes (Best for Cisco CCNA, Huawei HCNA, N+)

Follow our Facebook Page & YouTube Channel for more updated Cheatsheets & Quizzes :

Written by Arman Hasen

OSI Seven Layers Model Explained with Examples

This tutorial explains the OSI reference model. Learn the seven layers of the OSI model and the functions of each layer in detail through examples.

The OSI (Open System Interconnection) reference model is a comprehensive set of standards and rules for hardware manufacturers and software developers. By following these standards, they can build networking components and software applications that work in any environment. It was published in 1984 by ISO (International Organization for Standardization).

It provides a framework for creating and implementing networking standards, devices, and internetworking schemes. It explains the networking from a modular perspective, making it easier to understand and troubleshoot.

Seven layers of the OSI Model

The OSI model has seven different layers, which are divided into two groups. The following table lists all the layers with their names and numbers.

Group	Layer Number	Layer Name	Description
Top Layers	7	Application	Provide a user interface for sending and receiving data
	6	Presentation	Encrypt, format, and compress data for transmission
	5	Session	Initiate and terminate a session with the remote system
Bottom Layers	4	Transport	Break the data stream into smaller segments and provide reliable and unreliable data delivery
	3	Network	Provide logical addressing
	2	Data Link	Prepare data for transmission
	1	Physical	Move data between devices

Let’s understand each layer in detail.

This tutorial is the second part of the article " Networking reference models explained in detail with examples. ". Other parts of this article are the following.

This tutorial is the first part of the article. It summarizes why the OSI model was created and what advantages it has.

This tutorial is the third part of the article. It compares the OSI reference model with the TCP/IP model and lists the similarities and differences between both.

This tutorial is the fourth part of the article. It explains the five layers of the TCP/IP model in detail.

This tutorial is the fifth part of the article. It explains how data is encapsulated and de-encapsulated when it passes through the layers.

The Application Layer

This is the last and topmost layer of the OSI model. This layer provides an interface between the local system and the application program running on the network. If an application wants to use the resources available on the remote system, it interacts with this layer. Then, this layer provides the protocols and services that the application needs to access those resources.

There are two types of application programs: Network-aware and Network-unaware . An application program is considered a Network-aware application if it can make any type of network request. If an application program cannot make any type of network request, it is considered a Network-unaware program.

Network-aware programs are further divided into two types.

Programs that are mainly built to work on a local system. This type of program occasionally accesses the network for particular reasons such as updates, documentation, and troubleshooting. MS-Word, Adobe-Photoshop, and VLC Player are examples of this type of program.

Programs that are mainly built to work with a remote system. This type of program provides a platform to access resources available on a remote system. This type of program only works if the system is connected to the network. SSH, FTP, and TFTP are examples of this type of program.

The Application layer describes only the programs which fall in the second type. But it doesn’t mean that the first type of programs can’t take the advantage of the Application layer. It simply means that they are not documented in the Application layer. But if required, they can also connect to the network through the Application layer.

The Top layer of the OSI model is the application layer. It provides the protocols and services that are required by the network-aware applications to connect to the network. FTP, TFTP, POP3, SMTP, and HTTP are examples of standards and protocols used in this layer.

The Presentation Layer

The sixth layer of the OSI model is the Presentation layer. Applications running on the local system may or may not understand the format that is used to transmit the data over the network. The presentation layer works as a translator. When receiving data from the Application layer, it converts that data in such a format that can be sent over the network. When receiving data from the Session layer, it reconverts the data in such a format that the application, which will use it, can understand.

Conversion, compression, and encryption are the main functions that the Presentation layer performs on the sending computer while on the receiving computer these functions are reconversion, decompression, and decryption. ASCII, BMP, GIF, JPEG, WAV, AVI, and MPEG are examples of standards and protocols that work in this layer.

The Session Layer

The session layer is the fifth layer of the OSI model. It is responsible for setting up, managing, and dismantling sessions between presentation layer entities and providing dialogs between computers.

When an application makes a network request, this layer checks whether the requested resource is available on the local system or on a remote system. If the requested resource is available on a remote system, it tests whether a network connection to access that resource is available or not. If a network connection is not available, it sends an error message back to the application informing that the connection is not available.

If a network connection is available, it establishes a session with the remote system. For each request, it uses a separate session. This allows multiple applications to send or receive data simultaneously. When data transmission is completed, it terminates the session.

The session layer is responsible for establishing, managing, and terminating communications between two computers. RPCs and NFS are examples of the session layer.

The Transport Layer

The transport layer is the fourth layer of the OSI model. It provides the following functionalities: -

Segmentation

On the sending computer, it breaks the data stream into smaller pieces. Each piece is known as a segment and the process of breaking the data stream into smaller pieces is known as the segmentation . On the receiving computer, it joins all segments to recreate the original data stream.

Data transportation

This layer establishes a logical connection between the sending system and receiving system and uses that connection to provide end-to-end data transportation. This process uses two protocols: TCP and UDP.

The TCP protocol is used for reliable data transportation. TCP is a connection-oriented protocol. UDP protocol is used for unreliable data transportation. UDP is a connection-less protocol.

The main difference between a connection-less and connection-oriented protocol is that a connection-oriented protocol provides reliable data delivery. For reliable data delivery, it uses several mechanisms such as the three-way handshake process, acknowledgments, sequencing, and flow control.

Multiplexing

Through the use of port numbers, this layer also provides connection multiplexing. Connection multiplexing allows multiple applications to send and receive data simultaneously.

The main functionalities of the Transport layer are segmentation, data transportation, and connection multiplexing. For data transportation, it uses TCP and UDP protocols. TCP is a connection-oriented protocol. It provides reliable data delivery.

The Network Layer

The third layer of the OSI model is the Network Layer. This layer takes the data segment from the Transport layer and adds a logical address to it. A logical address has two components; network partition and host partition. The Network partition is used to group networking components while the host partition is used to uniquely identify a system on the network. A logical address is known as the IP address. Once the logical address and other related information are added to the segment , it becomes the packet .

This layer decides whether the packet is intended for the local system or a remote system. It also specifies the standards and protocols which are used to move data packets over networks.

To move data packets between two different networks, a device known as the router is used. Routers use the logical address to make the routing decision. Routing is the process of forwarding data packets to their destination.

Defining logical addresses and finding the best path to reach the destination address are the main functions of this layer. Routers work in this layer. Routing also takes place in this layer. IP, IPX, and AppleTalk are examples of this layer.

The Data Link Layer

The Data Link Layer is the second layer of the OSI model. This layer defines how networking components access the media and what transmission methods they use. This layer has two sub-layers: MAC and LLC.

MAC (Media Access Control)

This sub-layer defines how the data packets are placed in media. It also provides physical addressing. The physical address is known as the MAC address. Unlike logical addresses that need to be configured, physical addresses are pre-configured in NIC. The MAC address is used to uniquely identify a host in the local network.

LLC (Logical Link Control)

This sub-layer identifies the network layer protocol. On the sending computer, it encapsulates the information of the Network Layer protocol in the LLC header from which the Data Link layer receives the data packet. On the receiving computer, it checks the LLC header to get the information about the network layer protocol. This way, a data packet is always delivered to the same network layer protocol from which it was sent.

Defining physical addresses, finding hosts in the local network, specifying standards and methods to access the media are the primary functions of this layer. Switching takes place in this layer. Switches and Bridges work in this layer. HDLC, PPP, and Frame Relay are examples of this layer.

The Physical Layer

The Physical Layer is the first layer of the OSI model. This layer specifies the standards for devices, media, and technologies that are used in moving the data across the network such as:-

Type of cable used in connecting the devices
Patterns of pins used in both sides of the cable
Type of interface-card used in the networking device
Type of connector used to connect the cable with the network interface
Encoding of digital signals received from the Data Link layer based on the attached media type such as electrical for copper, light for fiber, or a radio wave for wireless.

On the sending computer, it converts digital signals received from the Data Link layer, into analog signals and loads them on the physical media. On the receiving computer, it picks analog signals from the media and converts them into digital signals, and transfers them to the Data Link layer for further processing.

The Physical Layer mainly defines standards for media and devices that are used to move data across the network. 10BaseT, 10Base100, CSU/DSU, DCE, and DTE are examples of the standards used in this layer.

That’s all for this tutorial. In the next part of this article, we will compare the OSI model with the TCP/IP model and explains the similarities and differences between both models. If you like this tutorial, please don’t forget to share it with friends.

By ComputerNetworkingNotes Updated on 2024-06-09

ComputerNetworkingNotes CCNA Study Guide OSI Seven Layers Model Explained with Examples

EtherChannel Load Distribution Explained
Link Aggregation Control Protocol (LACP) Explained
Port Aggregation Protocol (PAgP) Explained
EtherChannel Manual Configuration
EtherChannel Basic Concepts Explained
STP, RSTP, PVST, RPVST, and MSTP
Similarities and Differences between STP and RSTP
RSTP / RPVST Explained with Examples
PVST/RPVST and EtherChannel Explained
STP/RSTP Timers Explained

We do not accept any kind of Guest Post. Except Guest post submission, for any other query (such as adverting opportunity, product advertisement, feedback, suggestion, error reporting and technical issue) or simply just say to hello mail us [email protected]

Presentation Layer: Protocols, Examples, Services | Functions of Presentation Layer

Presentation Layer is the 6th layer in the Open System Interconnection (OSI) model where all application programmer consider data structure and presentation, beyond of simply sending the data into form of datagram otherwise packets in between the hosts. Now, we will explain about what is presentation layer with its protocols, example, service ; involving with major functions of presentation Layer with ease. At the end of this article, you will completely educate about What is Presentation Layer in OSI Model without any hassle.

What is Presentation Layer?

Presentation layer is capable to handle abstract data structures, and further it helps to defined and exchange of higher-level data structures.

Presentation Layer Tutorial Headlines:

Let’s get started, functions of presentation layer.

Presentation layer performs various functions in the OSI model ; below explain each one –

Protocols of Presentation Layer

Example of presentation layer protocols:.

Here, we will discuss all examples of presentation layer protocols; below explain each one –

Multipurpose Internet Mail Extensions (MIME) : MIME protocol was introduced by Bell Communications in 1991, and it is an internet standard that provides scalable capable of email for attaching of images, sounds and text in a message.

Network News Transfer Protocol (NNTP) : This protocol is used to make connection with Usenet server and transmit all newsgroup articles in between system over internet.

Apple Filing Protocol (AFP ) : AFP protocol is designed by Apple company for sharing all files over the entire network .

NetWare Core Protocol (NCP) : NCP is a Novell client server model protocol that is designed especially for Local Area Network (LAN). It is capable to perform several functions like as file/print-sharing, clock synchronization, remote processing and messaging.

Network Data Representation (NDR) : NDR is an data encoding standard, and it is implement in the Distributed Computing Environment (DCE).

Tox : The Tox protocol is sometimes regarded as part of both the presentation and application layer , and it is used for sending peer-to-peer instant-messaging as well as video calling.

eXternal Data Representation (XDR) : This protocol provides the description and encoding of entire data, and it’s main goal is to transfer data in between dissimilar computer architecture.

Presentation Layer Services

Design issues with presentation layer, faqs (frequently asked questions), what is meant by presentation layer in osi model.

Presentation Layer is the 6th layer in the Open System Interconnection (OSI) model that is the lowest layer, where all application programmer consider data structure and presentation, beyond of simply sending the data into form of datagram otherwise packets in between the hosts.

What protocols are used in the presentation layer?

Can you explain some presentation layer examples, what are the main functions of the presentation layer, what are services of presentation layer in osi.

Presentation layer has a responsibility for formatting, translation, and delivery of the information for getting to process otherwise display .

Now, i hope that you have completely learnt about what is presentation layer with its protocols, example, service ; involving with major functions of presentation Layer with ease. If this post is useful for you, then please share it along with your friends, family members or relatives over social media platforms like as Facebook, Instagram, Linked In, Twitter, and more.

Also Read: Data Link Layer: Protocols, Examples | Functions of Data Link Layer

Physical Layer

Data link layer, network layer, routing algorithm, transport layer, application layer, application protocols, network security.

Interview Questions

The presentation layer is the 6 layer from the bottom in the OSI model. This layer presents the incoming data from the application layer of the sender machine to the receiver machine. It converts one format of data to another format of data if both sender and receiver understand different formats; hence this layer is also called the translation layer. It deals with the semantics and syntax of the data, so this layer is also called the syntax layer. It uses operations such as data compression, data encryption & decryption, data conversion, etc.

Data is sent from sender to receiver, but what if the sender device and receiver device understand different formats of code? For example, suppose one device understands ASCII code and another device understands EBCDIC code. In that case, the data must be translated into a code that the recipient understands to determine what data has been sent. The presentation layer is responsible for translating ASCII codes to EBCDIC or vice versa. With the help of the presentation layer, the receiver understands the data effectively and uses it efficiently. Whatever data is being transmitted between the sender and the receiver, that data must be secure because an intruder can hack the data passing between the sender and the receiver. Hackers can modify the data and send the modified data to the receiver to create false communication. The presentation layer is responsible for encrypting and decrypting data to avoid data leakage and data modification.
The plaintext data at the source is encrypted into ciphertext (unreadable format), then it is sent to the receiver, where the ciphertext is decrypted into plaintext. Now, if the hacker tries to hack the data, the hacker receives an encrypted, unreadable form, and if the hacker tries to send modified data, the receiver can detect the modification during decryption; thereby, the data remains safe. If the file size is large, it becomes difficult to transmit the large file over the network. File size can be decreased by compressing the file for easy transmission of data. Compression is the method of diminishing the size of a file to transmit data easily in less time. When the compressed data reaches the receiver, the data is reconstructed back to the original size, and this process is called decompression.

The presentation layer in the OSI model is classified into two sublayers:

This sublayer offers services to layer-7, i.e., the application layer, and requests services from layer-5, i.e., the session layer. It supports various application services, such as Reliable Transfer Service Element (RTSE), Remote Operation Service Element (ROSE), Association Control Service Element (ACSE), and Commitment Concurrency and Recovery (CCR). This sublayer offers application-specific protocols, such as Message Oriented Text Interchange Standard (MOTIS), Remote Database Access (RDA), File Transfer Access and Manager (FTAM), Common Management Information Protocol (CMIP), Virtual Terminal (VT), Distributed Transaction Processing (DTP), Job Transfer and Manipulation (JTM), and others. It is a presentation layer protocol in the OSI model, which was formed by Citrix Systems. It is used for transferring data from server to client. It is a very thin protocol as it does not require much overhead in order to transmit data from the server over to the client. It is well-optimized for the WAN. It is the protocol that is used to implement the presentation layer of the OSI model. It provides different kinds of data representation, such as images, video, audio, numbers, etc. It is used for Microsoft Remote Procedure Call (Microsoft RPC) and Distributed Computing Environment (DCE) / Remote Procedure Calls (RPC). It is a communication protocol that was specifically designed for macOS by Apple, Inc. It provides file services for Classic Mac OS and macOS. This protocol is used to share files over the network. It is a protocol that is associated with the client-server operating system. The user can access the directory, print, message, file, clock synchronization, etc., with the help of this protocol. It supports many platforms, such as Linux, Classic Mac OS, Windows NT, Mac OS X, and Microsoft Windows. It is a telecommunications equipment that splits a stream of data into separate packets and formats packet headers for asynchronous communication on X.25 networks. It receives packets from the network and converts them into a stream of data. The PAD provides many asynchronous terminal connectivities to a host computer. It is a computer network protocol that is used to transfer data between two systems. It was first published in 1987. XDR is used by various systems such as NDMP, Network File System, NetCDF, ZFS, Open Network Computer Remote Procedure Call, and others. It is a protocol that offers ISO presentation services over TCP/IP based networks. This protocol explains an approach to provide stream-line support for OSI over TCP/IP based networks.

Send your Feedback to [email protected]

Help Others, Please Share

Learn Latest Tutorials

Transact-SQL

Reinforcement Learning

R Programming

React Native

Python Design Patterns

Python Pillow

Python Turtle

Preparation

Verbal Ability

Company Questions

Trending Technologies

Artificial Intelligence

Cloud Computing

Data Science

Machine Learning

B.Tech / MCA

Data Structures

Operating System

Compiler Design

Computer Organization

Discrete Mathematics

Ethical Hacking

Computer Graphics

Software Engineering

Web Technology

Cyber Security

C Programming

Control System

Data Mining

Data Warehouse

OSI Presentation and Application Layers

Cite this chapter.

Paul D. Bartoli 3

Part of the book series: Applications of Communications Theory ((ACTH))

259 Accesses

This chapter discusses the Application and Presentation Layers of the Reference Model of Open Systems Interconnection (OSI) [1]. The Application and Presentation Layers perform functions necessary to exchange information between application processes; the Application Layer is concerned with the semantic aspects of the information exchange, while the Presentation Layer is concerned with the syntactic aspects. The ability to manage the semantic and syntactic elements of the information to be exchanged is key to ensuring that the information can be interpreted by the communicants.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Subscribe and save.

Get 10 units per month
Download Article/Chapter or eBook
1 Unit = 1 Article or 1 Chapter
Cancel anytime
Available as PDF
Read on any device
Instant download
Own it forever
Compact, lightweight edition
Dispatched in 3 to 5 business days
Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Unable to display preview. Download preview PDF.

Information-Centric Networks (ICN)

Communication Issues in the Internet of Things (IoT)

The Internet in IoT—OSI, TCP/IP, IPv4, IPv6 and Internet Routing

ISO 7498, “Information processing systems—Open Systems Interconnection—Basic Reference Model,” 1984. CCITT Recommendation X.200, “Reference model of open systems interconnection for CCITT applications,” 1984 (updated expected in 1988).

Google Scholar

ISO DIS 9545, “Information processing systems—Open Systems Interconnection—Application Layer structure,” September 1988.

ISO TR 9007, “Concepts and terminology for the conceptual schema and the information base,” 1985.

ISO 8649, “Information processing systems—Open systems interconnection—Service definition for the association control service element,” 1988. ISO 8650, “Information processing systems—Open systems interconnection—Protocol specification for the association control service element,” 1988. CCITT Recommendation X.217, “Association control service definition for open systems interconnection for CCITT applications,” 1988. CCITT Recommendation X.227, “Association control protocol specification for open systems interconnection for CCITT applications,” final text December, 1987.

ISO 8571, “Information processing systems—Open systems interconnection—File transfer, access, and management,” Parts 1–4, 1988.

ISO/DIS 9804, “Information processing systems”Open systems interconnection—Service definition for commitment, concurrency, and recovery,” 1988 (text in SC 21 N 2573, March, 1988). ISO DIS 9805, “Information processing systems—Open systems interconnection—Protocol specification for commitment, concurrency, and recovery,” 1988 (text in SC 21 N 2574, March, 1988). CCITT Recommendation X.237, “Commitment, concurrency, and recovery service definition,” Draft Text, 1988. CCITT Recommendation X.247, “Commitment, concurrency, and recovery protocol specification, Draft Text, 1988.

ISO DIS 9040, “Information processing systems—Open systems interconnection—Virtual terminal service—Basic class,” 1988 (text in SC 21 N 2615, March, 1988). ISO DIS 9041, “Information processing systems—Open systems interconnection—Virtual terminal protocol—Basic class,” 1988 (text in SC 21 N 2616, March, 1988).

ISO DIS 9066–1, “Reliable transfer service”, 1988 (text in SC 18 N 1408, March, 1988). ISO DIS 9066–2, “Reliable transfer protocol specification,” 1988 (text in SC 18 N 1409). CCITT Recommendation X.218, “Reliable transfer: Model and service definition,” 1988. CCITT Recommendation X.228, “Reliable transfer: Protocol specification,” 1988.

ISO DIS 9072–1, “Remote operations service,” 1988 (text in SC 18 N 1410, March, 1988). ISO DIS 9072–2, “Remote operations protocol specification,” 1988 (text in SC 18 N 1411, March, 1988). CCITT Recommendation X.219, “Remote operations: Model, notation, and service definition,” 1988. CCITT Recommendation X.229, “Remote operations: Protocol specification,” 1988.

ISO DIS 9594, “Information processing—Open systems interconnection—The directory,” parts 1–8, 1988 (text in SC 21 N 2751 through N 2758, April, 1988). CCITT X.500, “Series recommendations on directory,” November, 1987.

ISO DIS 10021, “Information processing—Text communication—Message oriented text interchange system,” 1988 (text in SC 18 N 1487 through N 1493, May, 1988). CCITT X.400, “Series recommendations for message handling systems,” 1988.

ISO 8613/1–8, “Office document architecture and interchange format,” 1988, awaiting publication. CCITT T.400, “Series recommendations for document architecture, transfer, and manipulation,” 1988.

ISO 8824, “Information processing systems—Open systems interconnection—Specification of abstract syntax notation one (ASN.1),” 1987; and ISO 8824/PDAD 1, “Information processing systems—Open systems interconnection—Specification for ASN.1: Proposed draft Addendum 1 on ASN.1 extensions,” 1988 (final text in SC 21 N 2341 Revised, April, 1988). CCITT Recommendation X.208, “Specification of abstract syntax notation one (ASN.1),” 1988.

ISO 8822, “Information processing systems—Open systems interconnection—Connection oriented presentation service definition,” 1988. CCITT Recommendation X.216, “Presentation service definition for open systems interconnection for CCITT applications,” 1988.

ISO 8825, “Information processing—Open systems interconnection—Specification of basic encoding rules for abstract syntax notation one (ASN.1),” 1987; and ISO 8825/ PDAD 1, “Information processing systems—Open systems interconnection—Specification of basic encoding rules for ASN.1: Proposed draft addendum 1 on ASN.1 extensions,” 1988 (text in SC 21 N 2342 Revised, April, 1988). CCITT Recommendation X.209, “Specification of basic encoding rules for abstract syntax notation one (ASN.1),” 1988.

ISO 8823, “Information processing systems—Open systems interconnection—Connection oriented presentation protocol specification,” 1988. CCITT Recommendation X.226, “Presentation protocol specification for open systems interconnection for CCITT applications,” 1988.

ISO 8326, “Information processing systems—Open systems interconnection—Basic connection oriented session service definition,” 1987; and ISO 8326/AD 2, “Information processing systems—Open systems interconnection—Basic connection oriented session service definition—Addendum 2: Incorporation of unlimited user data,” 1988. ISO 8327, “Information processing systems—Open systems interconnection—Basic connection oriented session protocol specification,” 1987; and ISO 8327/AD 2, “Information processing systems—Open systems interconnection—Basic connection oriented session protocol specification—Addendum 2: Unlimited session user data protocol specification,” 1988.

CCITT Recommendation X.215, “Session service definition for open systems interconnection for CCITT applications,” 1988. CCITT Recommendation X.225, “Session protocol specification for open systems interconnection for CCITT applications,” 1988.

Download references

Author information

Authors and affiliations.

AT&T Bell Laboratories, 07733, Holmdel, New Jersey, USA

Paul D. Bartoli

You can also search for this author in PubMed Google Scholar

Editor information

Editors and affiliations.

Unisys West Coast Research Center, Santa Monica, 90406, California, USA

Carl A. Sunshine

Rights and permissions

Reprints and permissions

Copyright information

About this chapter

Bartoli, P.D. (1989). OSI Presentation and Application Layers. In: Sunshine, C.A. (eds) Computer Network Architectures and Protocols. Applications of Communications Theory. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-0809-6_13

Download citation

DOI : https://doi.org/10.1007/978-1-4613-0809-6_13

Publisher Name : Springer, Boston, MA

Print ISBN : 978-1-4612-8093-4

Online ISBN : 978-1-4613-0809-6

eBook Packages : Springer Book Archive

Share this chapter

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

Publish with us

Policies and ethics

Find a journal
Track your research

Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers
Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand
OverflowAI GenAI features for Teams
OverflowAPI Train & fine-tune LLMs
Labs The future of collective knowledge sharing
About the company Visit the blog

Collectives™ on Stack Overflow

Find centralized, trusted content and collaborate around the technologies you use most.

Q&A for work

Connect and share knowledge within a single location that is structured and easy to search.

Get early access and see previews of new features.

OSI model - What's the presentation and session layer for?

So I feel I pretty well understand the application layer, and everything below (and including) the transport layer.

The session and presentation layers, though, I don't fully understand. I've read the simplistic descriptions in Wikipedia, but it doesn't have an example of why separating out those layers is useful.

What is the session layer? What does it do, and under what circumstances is it better to have a session layer than simply talk to the transport with your app?
What is the presentation layer? (same questions as above)

7 Answers 7

The session layer is meant to store states between two connections, like what we use cookies for when working with web programming.

The presentation layer is meant to convert between different formats. This was simpler when the only format that was worried about was character encoding, ie ASCII and EBCDIC. When you consider all of the different formats that we have today(Quicktime, Flash, Pdf) centralizing this layer is out of the question.

TCP/IP doesn't make any allocation to these layers, since they are really out of the scope of a networking protocol. It's up to the applications that take advantage of the stack to implement these.

The reasons there aren't any examples on wikipedia is that there aren't a whole lot of examples of the OSI network model, period.

OSI has once again created a standard nobody uses, so nobody really know how one should use it.

Layers 5-6 are not commonly used in today's web applications, so you don't hear much about them. The TCP/IP stack is slightly different than a pure OSI Model.

One of the reasons TCP/IP is used today instead of OSI is it was too bloated and theoretical, the session and presentation layer aren't really needed as separate layers as it turned out.

I think that presentation layer protocols define the format of data. This means protocols like XML or ASN.1. You could argue that video/audio codecs are part of the presentation layer Although this is probably heading towards the application layer.

I can't help you with the session layer. That has always baffled me.

To be honest, there are very vague boundaries in everything above the transport layer. This is because it is usually handled by a single software application. Also, these layers are not directly associated with transporting data from A to B. Layers 4 and below each have a very specific purpose in moving the data e.g. switching, routing, ensuring data integrity etc. This makes it easier to distinguish between these layers.

Presentation Layer The Presentation Layer represents the area that is independent of data representation at the application layer - in general, it represents the preparation or translation of application format to network format, or from network formatting to application format. In other words, the layer “presents” data for the application or the network. A good example of this is encryption and decryption of data for secure transmission - this happens at Layer 6.

Session Layer When two devices, computers or servers need to “speak” with one another, a session needs to be created, and this is done at the Session Layer. Functions at this layer involve setup, coordination (how long should a system wait for a response, for example) and termination between the applications at each end of the session.

For the presentation layer :because most of communication done between heterogeneous systems (Operating Systems,programing langages,cpu architectures)we need to use a unified idepedent specification .like ANS1 ans BRE.

Your Answer

Reminder: Answers generated by artificial intelligence tools are not allowed on Stack Overflow. Learn more

Sign up or log in

Post as a guest.

Required, but never shown

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy .

Not the answer you're looking for? Browse other questions tagged networking model stack osi or ask your own question .

The Overflow Blog
Ryan Dahl explains why Deno had to evolve with version 2.0
From PHP to JavaScript to Kubernetes: how one backend engineer evolved over time
Featured on Meta
We've made changes to our Terms of Service & Privacy Policy - July 2024
Bringing clarity to status tag usage on meta sites
Feedback requested: How do you use tag hover descriptions for curating and do...
What does a new user need in a homepage experience on Stack Overflow?

Hot Network Questions

Efficiently tagging first and last of each object matching condition
Why do combinatorists care about Kazhdan–Lusztig polynomials?
Which translation of Psalm 113:9 is closest to the original?
Can I use rear (thru) axle with crack for a few rides, before getting a new one?
Name of engineering civil construction device for flattening tarmac
"Knocking it out of the park" sports metaphor American English vs British English?
Do cities usually form at the mouth of rivers or closer to the headwaters?
Why don't we observe protons deflecting in J.J. Thomson's experiment?
If Miles doesn’t consider Peter’s actions as hacking, then what does he think Peter is doing to the computer?
Short story in which the protagonist shrinks to the size of his model train set and is run over by one of his trains
What does the Fizeau experiment now do?
grep command fails with out-of-memory error
How to determine if a set is countable or uncountable?
Has the government of Afghanistan clarified what they mean/intend by the ban on 'images of living beings'?
Are Experimental Elixirs Magic Items?
How would I make an agent noun out of the word "autodice -es f" or "autodicia"
Postdoc supervisor has stopped helping
Non decreasing function for utility transformation
Is there anything that stops the majority shareholder(s) from destroying company value?
Can a "sharp turn" on a trace with an SMD resistor also present a risk of reflection?
What's the Matter?
How can I address my colleague communicating with us via chatGPT?
What is the lesson of the Book of Iyov for the "average" person
One IO to control two LEDs. When one is lit, the other is not

COMMENTS

Presentation Layer in OSI model
Prerequisite : OSI Model Introduction : Presentation Layer is the 6th layer in the Open System Interconnection (OSI) model. This layer is also known as Translation layer, as this layer serves as a data translator for the network. The data which this layer receives from the Application Layer is extracted and manipulated here as per the required format to transmit over the network.
Presentation layer
The presentation layer ensures the information that the application layer of one system sends out is readable by the application layer of another system. On the sending system it is responsible for conversion to standard, transmittable formats. [ 7] On the receiving system it is responsible for the translation, formatting, and delivery of ...
Presentation Layer
OSI Layer 6 - Presentation Layer. The presentation layer is responsible for the delivery and formatting of information to the application layer for further processing or display. It relieves the application layer of concern regarding syntactical differences in data representation within the end-user systems. An example of a presentation service ...
The OSI Model
The Session Layer initiates, maintains, and terminates connections between two end-user applications. It responds to requests from the presentation layer and issues requests to the transport layer. OSI Layer 6. Layer 6 is the presentation layer. This layer is responsible for data formatting, such as character encoding and conversions, and data ...
Presentation Layer
Presentation Layer functions. Translation: Before being transmitted, information in the form of characters and numbers should be changed to bit streams.Layer 6 is responsible for interoperability between encoding methods as different computers use different encoding methods.
Presentation Layer: What It Is, Design Issues, Functionalities
Functionalities of the Presentation Layer. Specific functionalities of the presentation layer are as follows: 1. Translation. The processes or running programs in two machines are usually exchanging the information in the form of numbers, character strings and so on before being transmitted. The information should be changed to bitstreams ...
Presentation layer and Session layer of the OSI model
The presentation layer is the sixth layer of the OSI Reference model. It defines how data and information is transmitted and presented to the user. It translates data and format code in such a way that it is correctly used by the application layer. It identifies the syntaxes that different applications use and formats data using those syntaxes.
What is presentation layer?
The presentation layer is located at Layer 6 of the OSI model. The tool that manages Hypertext Transfer Protocol ( HTTP) is an example of a program that loosely adheres to the presentation layer of OSI. Although it's technically considered an application-layer protocol per the TCP/IP model, HTTP includes presentation layer services within it.
A Guide to the Presentation Layer
Understanding the layers of the Open Systems Interconnect (OSI) model can help users conceptualize data communication over a network. Layer 6 in the OSI model - the presentation layer - translates, compresses, and encrypts data across networks. In this article, we'll explain what the presentation layer is, how it works, and its functions and protocols.
Presentation Layer of OSI Reference Model
The presentation layer manages these abstract data structures and allows higher-level data structures(eg: banking records), to be defined and exchanged. Functions of Presentation Layer. Translation: Before being transmitted, information in the form of characters and numbers should be changed to bit streams. The presentation layer is responsible ...
What is Presentation Layer in the OSI Model?
Key functions of the Presentation Layer in the OSI model include: Data Encryption: It securely encrypts data to prevent unauthorized access during transmission. Data Compression: It reduces data ...
PDF Presentation Layer
The presentation layer is concerned with preserving the meaning of information sent across a network. The presentation layer may represent (encode) the data in various ways (e.g., data compression, or encryption), but the receiving peer will convert the encoding back into its original meaning. The presentation layer concerns itself with the ...
What is the presentation layer?
The presentation layer interacts closely with the application layer, which is located directly above it. The presentation layer's main task is to present data in such a way that it can be understood and interpreted from both the system sending the data and the system receiving it. After this has been accomplished, the application layer then determines how the data should be structured and ...
Presentation Layer In OSI Model : A Comprehensive Guide
The Presentation Layer, within the OSI (Open Systems Interconnection) model, is the sixth layer. It focuses on the representation of data, ensuring that information exchanged between applications is formatted appropriately for transmission and receipt across a network. This layer handles tasks such as data translation, encryption, compression ...
The OSI Model: Layer 6
The Presentation Layer gets its name from its purpose: It presents data to the Application layer. It's basically a translator and provides coding and conversion functions. A successful data transfer technique is to adapt the data into a standard format before transmission. Computers are configured to receive this generically formatted data and ...
Presentation Layer of OSI Model (Layer-6)
Presentation Layer is responsible for representation & formatting of data for session Layer in encapsulation process. It is the 6th Layer in the seven layer OSI Model after Session Layer. Presentation layer serves like a translator & takes care that the data is sent in such a way that the receiver will understand the information or data and will be able to use the data.
OSI Seven Layers Model Explained with Examples
The Presentation Layer. The sixth layer of the OSI model is the Presentation layer. Applications running on the local system may or may not understand the format that is used to transmit the data over the network. The presentation layer works as a translator. When receiving data from the Application layer, it converts that data in such a format ...
Presentation Layer of the OSI Model
The presentation layer is a very important layer because it handles encryption, decryption, and the conversion of complex data into flat-byte strings, a format that is easily transmittable. The ...
Presentation Layer: Protocols, Examples, Services
What is Presentation Layer? Definition: Presentation layer is 6th layer in the OSI model, and its main objective is to present all messages to upper layer as a standardized format.It is also known as the "Translation layer". This layer takes care of syntax and semantics of messages exchanged in between two communication systems. Presentation layer has responsible that receiver can ...
Presentation Layer in OSI Model
The presentation layer is the 6 th layer from the bottom in the OSI model. This layer presents the incoming data from the application layer of the sender machine to the receiver machine. It converts one format of data to another format of data if both sender and receiver understand different formats; hence this layer is also called the ...
PDF 13 OSI Presentation and Application Layers
13. ion LayersPaul D. BartoliI. IntroductionThis chapter discusses the Application and Presentation Layers of the Reference Model. of Open Systems Interconnection (OSI) [1]. The Applica tion and Presentation Layers perform functions necessary to exchange information between application processes; the Application Layer is con cerned with the ...
OSI model
The session layer is meant to store states between two connections, like what we use cookies for when working with web programming. The presentation layer is meant to convert between different formats. This was simpler when the only format that was worried about was character encoding, ie ASCII and EBCDIC. When you consider all of the different ...
What is the OSI Model? An Overview of the OSI Model's 7 Layers
1. Application Layer This is the layer where humans interact with computers. It consists of end-user software such as browsers, messengers, and email client applications. This layer communicates with the presentation layer to receive information from it so it can be given to the end user.

Presentation Layer in OSI model

Please Login to comment...

Improve your Coding Skills with Practice

What kind of Experience do you want to share?

Layer 6 Presentation Layer

OSI Layer 6 - Presentation Layer

CASE common application service element

SASE specific application service element

Layer 7 Application Layer

The OSI Model – The 7 Layers of Networking Explained in Plain English

Prerequisites

Learning Objectives

Common Networking Terms

What is the OSI Model?

OSI Layer 1

How to Troubleshoot OSI Layer 1 Problems

OSI Layer 2

How to Troubleshoot OSI Layer 2 Problems

OSI Layer 3

How to Troubleshoot OSI Layer 3 Problems

OSI Layer 4

How to Troubleshoot OSI Layer 4 Problems

OSI Layer 5

How to Troubleshoot OSI Layer 5 Problems

OSI Layer 6

How to Troubleshoot OSI Layer 6 Problems

OSI Layer 7

How to Troubleshoot OSI Layer 7 Problems

Learning Resources

Presentation Layer

What is the Presentation Layer?

Presentation Layer functions

Role of Presentation Layer in the OSI Model

Explaining Layer 6 in video

In short, the presentation layer

Computer Network Tutorial

Difference B/W Articles

Computer Network Practice

Presentation Layer: What It Is, Design Issues, Functionalities

What is Presentation Layer?

Design Issues with Presentation Layer

Functionalities of the Presentation Layer

1. Translation

2. Encryption

3. Compression

presentation layer

What is the presentation layer?

How the presentation layer works

Functions of the presentation layer

Continue Reading About presentation layer

Related Terms

What are the most important email security protocols?

file extension (file format)

network protocol

MIME (Multipurpose Internet Mail Extensions)

COMPUTER NETWORK BASICS

Physical Layer

Data link layer

Transport layer

ISO/OSI REFERENCE MODEL

TCP/IP REFERENCE MODELCOMPUTER NETWORKS

Session layer

Computer Networks

Presentation layer

Application layer

Presentation Layer - OSI Model

Functions of Presentation Layer

Design Issues with Presentation Layer

CN MCQ Tests

What is Presentation Layer in the OSI Model?

Introduction to the Presentation Layer

Presentation Layer Functions

Protocols at the Presentation Layer

Final Words

Written by InfosecTrain

Presentation Layer In OSI Model : A Comprehensive Guide

What is the Presentation Layer?

Working of Presentation Layer

Functions of the Presentation Layer

Please Share This Share this content