presentation layer what does it do

• 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.

Similar Reads

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

Sase specific application service element, 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.

Computer Network

• Introduction
• Architecture
• Computer Network Types
• Transmission Modes
• TCP/IP Model

Physical Layer

• Digital Transmission
• Transmission Media
• Guided Media
• UnGuided Media
• Multiplexing
• Switching Modes
• Switching Techniques
• Data Link layer
• Error Detection
• Error Correction
• Data Link Controls
• Network Layer
• Network Addressing
• Network Layer Protocols
• Routing Algorithm
• Distance Vector
• Link State Routing
• Transport Layer
• Transport Layer Protocols
• Application Layer
• Client & Server Model

Application Protocols

Network security.

• Digital Signature
• What is Router
• OSI vs TCP/IP
• IPv4 vs IPv6
• ARP Packet Format
• Working of ARP
• FTP Commands
• I2P Protocol
• Sliding Window Protocol
• SPI Protocol
• ARP Commands
• ARP Request
• ARP - Address Resolution Protocol
• ARP and its types
• TCP Retransmission
• CAN Protocol
• HTTP Status Codes
• HTTP vs HTTPS
• RIP Protocol
• UDP Protocol
• ICMP Protocol
• MQTT Protocol
• OSPF Protocol
• Stop & Wait Protocol
• IMAP Protocol
• POP Protocol
• Go-Back-N ARQ
• Connection-Oriented vs Connectionless Service
• CDMA vs GSM
• What is MAC Address
• Modem vs Router
• Switch vs Router
• USB 2.0 vs USB 3.0
• CSMA CA vs CSMA CD
• Multiple Access Protocols
• IMAP vs. POP3
• SSH Meaning
• Status Code 400
• MIME Protocol
• What is a proxy server and how does it work
• How to set up and use a proxy server
• What is network security
• WWW is based on which model
• Proxy Server List
• Fundamentals of Computer Networking
• IP Address Format and Table
• Bus topology vs Ring topology
• Bus topology vs Star topology
• Circuit Switching vs Packet switching
• star vs ring topology
• Router vs Bridge
• TCP Connection Termination
• Image Steganography
• Network Neutrality
• Onion Routing
• ASA features
• Relabel-to-front Algorithm
• Types of Server Virtualization in Computer Network
• Access Lists (ACL)
• Digital Subscriber Line (DSL)
• Operating system based Virtualization
• Context based Access Control (CBAC)
• Cristian's Algorithm
• Service Set Identifier (SSID) in Computer Network
• Voice over Internet Protocol (VoIP)
• Challenge Response Authentication Mechanism (CRAM)
• Extended Access List
• Li-fi vs. Wi-fi
• Reflexive Access List
• Synchronous Optical Network (SONET)
• Wifi protected access (WPA)
• Wifi Protected Setup (WPS)
• Standard Access List
• Time Access List
• What is 3D Internet
• 4G Mobile Communication Technology
• Types of Wireless Transmission Media
• Best Computer Networking Courses
• Data Representation
• Network Criteria
• Classful vs Classless addressing
• Difference between BOOTP and RARP in Computer Networking
• What is AGP (Accelerated Graphics Port)
• Advantages and Disadvantages of Satellite Communication
• External IP Address
• Asynchronous Transfer Mode (ATM) in Computer Network
• Types of Authentication Protocols
• What is a CISCO Packet Tracer
• How does BOOTP work
• Subnetting in Computer Networks
• Mesh Topology Advantages and Disadvantages
• Ring Topology Advantages and Disadvantages
• Star Topology Advantages and Disadvantages
• Tree Topology Advantages and Disadvantages
• Zigbee Technology-The smart home protocol
• Network Layer in OSI Model
• Physical Layer in OSI Model
• Data Link Layer in OSI Model
• Internet explorer shortcut keys
• Network Layer Security | SSL Protocols
• Presentation Layer in OSI Model
• Session Layer in OSI Model
• SUBNET MASK
• Transport Layer Security | Secure Socket Layer (SSL) and SSL Architecture
• Functions, Advantages and Disadvantages of Network Layer
• Functions, Advantages and Disadvantages of the Physical Layer
• Types of Internet Connection
• Noisy and Noiseless Channel
• Advantages and Disadvantages of Bus Topology
• Advantages and Disadvantages of Ring Topology
• Advantages and Disadvantages of Star Topology
• Protocols in Noiseless and Noisy Channel
• Advantages and Disadvantages of Mesh Topology
• Cloud Networking - Managing and Optimizing Cloud-Based Networks
• Collision Domain and Broadcast Domain
• Count to Infinity Problem in Distance Vector Routing
• Difference Between Go-Back-N and Selective Repeat Protocol
• Difference between Stop and Wait, GoBackN, and Selective Repeat
• Network Function Virtualization (NFV): transforming Network Architecture with Virtualized Functions
• Network-Layer Security | IPSec Modes
• Network-Layer Security | IPSec Protocols and Services
• Ping vs Traceroute
• Software Defined Networking (SDN): Benefits and Challenges of Network Virtualization
• Software Defined Networking (SDN) vs. Network Function Virtualization (NFV)
• Virtual Circuits vs Datagram Networks
• BlueSmack Attack in Wireless Networks
• Bluesnarfing Attack in Wireless Networks
• Direct Sequence Spread Spectrum
• Warchalking in Wireless Networks
• WEP (Wired Equivalent Privacy)
• Wireless security encryption
• Wireless Security in an Enterprise
• Quantum Networking
• Network Automation
• Difference between MSS and MTU
• What is MTU
• Mesh Networks: A decentralized and Self-Organizing Approach to Networking
• What is Autonomous System
• What is MSS
• Cyber security and Software security
• Information security and Network security
• Security Engineer and Security Architect
• Protection Methods for Network Security
• Trusted Systems in Network Security
• What are Authentication Tokens in Network security
• Cookies in Network Security
• Intruders in Network Security
• Network Security Toolkit (NST) in virtual box
• Pivoting-Moving Inside a Network
• Security Environment in Computer Networks
• Voice Biometric technique in Network Security
• Advantages and Disadvantages of Conventional Testing
• Difference between Kerberos and LDAP
• Cyber security and Information Security
• GraphQL Attacks and Security
• Application Layer in OSI Model
• Applications of Remote Sensing
• Seven Layers of IT Security
• What is Ad Hoc TCP
• What is Server Name Indication(SNI)
• Difference Between Infrastructure and Infrastructure Less Network
• Collision Avoidance in Wireless Networks
• Difference Engine and Analytical Engine
• Hotspot 2.0
• Intrusion Prevention System (IPS)
• Modes of Connection Bluetooth
• Noisy Channel protocols
• Parzen Windows density Estimation Technique
• Principle of Information System Security
• What are Bots, Botnets, and Zombies
• Windows Memory Management
• Wireless dos attack on Wifi
• Design Principles of Security in Distributed Systems
• MAC Filtering
• Principles of Network Applications
• Time-to-Live (TTL)
• What is 1000 BASE-T
• What is the difference between 802.11ac and 802.11ax
• Differentiate between Circuit Switching, Message Switching, and Packet Switching
• What is Web 3.0
• Collision Detection in CSMA/CD
• Ipv4 Header in Computer Networks
• Layered Architecture in Computer Networks
• Define URL in Computer Networks
• MAN in Computer Networks
• Routing Protocols in Computer Networks
• Flooding in Computer Network
• CRC in Computer Network
• Application of Computer Network
• Computer Network Architect
• Design Issues for the Layers of Computer Networks
• What is AMD (Advanced Micro Devices)
• Protocol in Computer Network
• Computer Network Projects
• Different Types of Routers
• Wireless Distribution System (WDS)
• Network Time Protocol
• Address Resolution Protocol (ARP) and its types in Computer Network
• Automatic Repeat ReQuest (ARQ) in Computer Networks
• Bluetooth in Computer Networks
• Circuit Switching in Computer Network
• Computer Hardware and Networking Course
• Ring Topology in a Computer Network
• Token Ring in Computer Networks
• Medium Access Control in Computer Network
• Need for Computer Network
• Repeater in Computer Network
• Computer Networking: a Top Down Approach
• What is Multiplexing in Computer Network
• Body Area Network (BAN)
• INS AND OUT OF DATA STREAMING
• Streaming stored video
• Cellular Network
• How can devices on a Network be identified
• How Does the Internet Work
• Authentication Server
• What is Cloud Backup and How does it Work
• Communication Protocols In System Design
• Extensible Authentication Protocol (EAP)
• Role-Based Access Control (RBAC)
• Network Enumeration Tools
• Network Protocol Testing
• Windows Networking Commands
• Advantages and Disadvantages of WLAN
• Anonymous File Transfer Protocol (AFTP)
• Automatic Private IP Addressing
• What is Deep Web
• USB-C (USB Type C)
• User Authentication
• What is a vCard
• ipv4 Headers
• Difference between Token ring and Ethernet Token Ring
• Server Message Block protocol (SMB protocol)
• Session Border Controllers (SBC)
• Short Message Service Center (SMSC)
• What is a Mail Server
• What are Communication Networks
• Initialization Vector
• What is Fiber Optics
• Open Networking
• Access Ports Vs Trunk Ports
• Edge Routers
• IPTV (Internet Protocol Television)
• Wireless Internet Service Provider (WISP)
• Wireless Backhaul
• Define Protocol in Computer Network
• Virtual Network Adapter
• Virtual Routing and Forwarding
• Virtual Switches(vSwitches)
• VLAN (Virtual LAN)
• Wireless Mesh Network (WMN)
• What is Gateway in Computer Network
• Radio Access Network (RAN)
• What is File Sharing
• Passive Optical Network (PON)
• Private IP address
• Public Key Certificate
• What is Bridge in Computer Network
• Ping Sweep (ICMP Sweep)
• Print Server
• WIFI Pineapple
• Walled Garden
• Wireless ISP (wireless Internet service provider or WISP)
• Bridge vs Repeater
• Hardware Security Module (HSM)
• Public Switched Telephone Network
• Analog Telephone Adapter (ATA)
• Host Bus Adapter (HBA)
• ISCSI initiator
• Simplest Protocol
• Telecommunication Networks
• What is WPS in Wi-Fi
• What are the Most Important Email Security Protocols
• What is Data Governance and Why does it Matter
• Carrier Network
• Most Secure Network Protocol
• Network SMB
• BGP vs. EIGRP: What's the Difference
• Wireless Security: WEP, WPA, WPA2 and WPA3 differences
• Cloud Radio Access Network (C-RAN)
• Bits Per Second (bps or bit/sec)
• Blade Server
• command-and-control server (C&C server)
• Computer Network MCQ
• Computer Network MCQ Part2

Interview Questions

• Networking Questions

Latest Courses

We provides tutorials and interview questions of all technology like java tutorial, android, java frameworks

Contact info

G-13, 2nd Floor, Sec-3, Noida, UP, 201301, India

[email protected] .

Latest Post

PRIVACY POLICY

Online Compiler

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.

Related Tutorials

• IPV4 Addressing | Classful and Classless Addressing
• Subnetting and Supernetting in Computer Network
• Network Address Translation (NAT) in Computer Network
• Fixed Length and Variable Length Subnet Mask (FLSM & VLSM)
• Line Configuration in Computer Network
• Transmission Modes in Computer Network
• Data Link Layer: What It Is, Sublayers, Design Issues, Functions
• Physical Layer: What It Is, Design Issues, Functions
• Network Layer: What It Is, Design Issues, Responsibilities
• Session Layer: What It Is, Design Issues, Functionalities
• Transport Layer: What It Is, Design Issues, Functions, and Example
• Optical Fiber (Fiber Optics) in Computer Network
• Unguided Transmission Media in Computer Network
• Virtual LAN (VLAN) in Computer Network
• Virtual Storage Area Networking (VSAN)

Comments and Discussions!

Load comments ↻

• Marketing MCQs
• Blockchain MCQs
• Artificial Intelligence MCQs
• Data Analytics & Visualization MCQs
• Python MCQs
• C++ Programs
• Python Programs
• Java Programs
• D.S. Programs
• Golang Programs
• C# Programs
• JavaScript Examples
• jQuery Examples
• CSS Examples
• C++ Tutorial
• Python Tutorial
• ML/AI Tutorial
• MIS Tutorial
• Software Engineering Tutorial
• Scala Tutorial
• Privacy policy
• Certificates
• Content Writers of the Month

Copyright © 2024 www.includehelp.com. All rights reserved.

How-To Geek

The 7 osi networking layers explained.

Your changes have been saved

Email is sent

Email has already been sent

You’ve reached your account maximum for followed topics.

Quick Links

• Physical Layer
• Data Link Layer
• Network Layer
• Transport Layer
• Session Layer
• Presentation Layer
• Application Layer

The Open Systems Interconnection (OSI) networking model defines a conceptual framework for communications between computer systems. The model is an ISO standard which identifies seven fundamental networking layers, from the physical hardware up to high-level software applications.

Each layer in the model handles a specific networking function. The standard helps administrators to visualize networks, isolate problems, and understand the use cases for new technologies. Many network equipment vendors advertise the OSI layer that their products are designed to slot into.

OSI was adopted as an international standard in 1984. It remains relevant today despite the changes to network implementation that have occurred since first publication. Cloud, edge, and IoT can all be accommodated within the model.

In this article, we'll explain each of the seven OSI layers in turn. We'll start from the lowest level, labelled as Layer 1.

1. Physical Layer

All networking begins with physical equipment. This layer encapsulates the hardware involved in the communications, such as switches and cables. Data is transferred as a stream of binary digits - 0 or 1 - that the hardware prepares from input it's been fed. The physical layer specifies the electrical signals that are used to encode the data over the wire, such as a 5-volt pulse to indicate a binary "1."

Errors in the physical layer tend to result in data not being transferred at all. There could be a break in the connection due to a missing plug or incorrect power supply. Problems can also arise when two components disagree on the physical encoding of data values. In the case of wireless connections, a weak signal can lead to bit loss during transmission.

2. Data Link Layer

The model's second layer concerns communication between two devices that are directly connected to each other in the same network. It's responsible for establishing a link that allows data to be exchanged using an agreed protocol. Many network switches operate at Layer 2.

The data link layer will eventually pass bits to the physical layer. As it sits above the hardware, the data link layer can perform basic error detection and correction in response to physical transfer issues. There are two sub-layers that define these responsibilities: Logical Link Control (LLC) that handles frame synchronization and error detection, and Media Access Control (MAC) which uses MAC addresses to constrain how devices acquire permission to transfer data.

3. Network Layer

The network layer is the first level to support data transfer between two separately maintained networks. It's redundant in situations where all your devices exist on the same network.

Data that comes to the network layer from higher levels is first broken up into packets suitable for transmission. Packets received from the remote network in response are reassembled into usable data.

The network layer is where several important protocols are first encountered. These include IP (for determining the path to a destination), ICMP, routing, and virtual LAN. Together these mechanisms facilitate inter-network communications with a familiar degree of usability. However operations at this level aren't necessarily reliable: messages aren't required to succeed and may not necessarily be retried.

4. Transport Layer

The transport layer provides higher-level abstractions for coordinating data transfers between devices. Transport controllers determine where data will be sent and the rate it should be transferred at.

Layer 4 is where TCP and UDP are implemented, providing the port numbers that allow devices to expose multiple communication channels. Load balancing is often situated at Layer 4 as a result, allowing traffic to be routed between ports on a target device.

Transport mechanisms are expected to guarantee successful communication. Stringent error controls are applied to recover from packet loss and retry failed transfers. Flow control is enforced so the sender doesn't overwhelm the remote device by sending data more quickly than the available bandwidth permits.

5. Session Layer

Layer 5 creates ongoing communication sessions between two devices. Sessions are used to negotiate new connections, agree on their duration, and gracefully close down the connection once the data exchange is complete. This layer ensures that sessions remain open long enough to transfer all the data that's being sent.

Checkpoint control is another responsibility that's held by Layer 5. Sessions can define checkpoints to facilitate progress updates and resumable transmissions. A new checkpoint could be set every few megabytes for a file upload, allowing the sender to continue from a particular point if the transfer gets interrupted.

Many significant protocols operate at Layer 5 including authentication and logon technologies such as LDAP and NetBIOS. These establish semi-permanent communication channels for managing an end user session on a specific device.

6. Presentation Layer

The presentation layer handles preparation of data for the application layer that comes next in the model. After data has made it up from the hardware, through the data link, and across the transport, it's almost ready to be consumed by high-level components. The presentation layer completes the process by performing any formatting tasks that may be required.

Decryption, decoding, and decompression are three common operations found at this level. The presentation layer processes received data into formats that can be eventually utilized by a client application. Similarly, outward-bound data is reformatted into compressed and encrypted structures that are suitable for network transmission.

TLS is one major technology that's part of the presentation layer. Certificate verification and data decryption is handled before requests reach the network client, allowing information to be consumed with confidence that it's authentic.

7. Application Layer

The application layer is the top of the stack. It represents the functionality that's perceived by network end users. Applications in the OSI model provide a convenient end-to-end interface to facilitate complete data transfers, without making you think about hardware, data links, sessions, and compression.

Despite its name, this layer doesn't relate to client-side software such as your web browser or email client. An application in OSI terms is a protocol that caters for the complete communication of complex data through layers 1-6.

HTTP, FTP, DHCP, DNS, and SSH all exist at the application layer. These are high-level mechanisms which permit direct transfers of user data between an origin device and a remote server. You only need minimal knowledge of the workings of the other layers.

The seven OSI layers describe the transfer of data through computer networks. Understanding the functions and responsibilities of each layer can help you identify the source of problems and assess the intended use case for new components.

OSI is an abstract model that doesn't directly map to the specific networking implementations commonly used today. As an example, the TCP/IP protocol works on its own simpler system of four layers: Network Access, Internet, Transport, and Application. These abstract and absorb the equivalent OSI layers: the application layer spans OSI L5 to L7, while L1 and L2 are combined in TCP/IP's concept of Network Access.

OSI remains applicable despite its lack of direct real-world application. It's been around so long that it's widely understood among administrators from all backgrounds. Its relatively high level of abstraction has also ensured it's remained relevant in the face of new networking paradigms, many of which have targeted Layer 3 and above. An awareness of the seven layers and their responsibilities can still help you appreciate the flow of data through a network while uncovering integration opportunities for new components.