Presentation Layer of the OSI Model: Definition and Function

The Presentation Layer, which makes up Layer 6 of the OSI Model, creates context between application-layer entities. Higher-layer entities may use different syntax and semantics in this context if the presentation service provides a mapping between them. Presentation service data units are wrapped in session protocol data units and passed down the stack if a mapping is available. This layer provides independence from data representation (e. g. , encryption) by translating between application and network formats. Data is transformed by the presentation layer into a format that the application can use. This layer prepares data for transmission across a network and encrypts it.

With its Secure Cloud-Managed Network Services, Infoblox is paving the way for next-generation DDI. Infoblox puts on-premises, cloud, and hybrid networks at the forefront of security, dependability, and automation, putting users on the road to a single pane of glass for network management. Infoblox, the well-known market pioneer, has more than 8,000 clients, including 350 Fortune 500 companies.

11 – Layer 6 (Presentation Layer)

Layers of the OSI model

There are seven layers of the OSI model. Understanding the other six layers can help you comprehend the presentation layer. The lower or media layers, which are the first three layers, control how data is transferred between computers. The top or host layers are the remaining layers, and they deal with how applications interact with networks. Since the seventh and topmost layer is the one you directly interact with, the OSI model’s layer order is reversed.

The OSI model’s layers, in addition to the presentation layer, are as follows:


The application layer, which is the topmost and seventh layer, allows users to input data and view data sent to them. The application layer is not where computer applications live, but rather it is where protocols are used to perform functions. Web browsers, for instance, use HTTP or HTTPS to send data to the presentation layer, which is located beneath the application layer. After that, it starts the process of connecting to a receiving computer.


The presentation layer is the fourth layer, and the session layer is the fifth layer. A session—a connection between the two computers—must be established before one can send data to the other. The web server is interacted with by the session layer to create and maintain this connection. Additionally, this layer is in charge of verifying a user’s identity, determining whether they have authorization to access the data they desire, and ending the session when it is complete.


The transport layer, the fourth and final host layer, is responsible for ensuring secure, error-free data transmission. The amount, rate, and destination of the data being transmitted are all determined by this layer. It divides the data from the session layer into manageable chunks, each of which contains information that directs its transmission. Once it reaches the recipient, it then correctly reassembles the data. A well-known protocol, TCP, resides in the transport layer.


Data packets from one computer to another are forwarded by the third layer, the network layer. This layer is responsible for routing, or choosing a network’s data flow path. There are many possible routes for data to take as it moves toward a destination, but the network layer enables it to choose the most effective path.

Data link

The data link layer, the second layer, carries out a few crucial tasks. It does this primarily by addressing each packet of data so that it is transmitted to the intended recipient and by managing transmission traffic to prevent data collisions from occurring when multiple nodes or connection points transmit data at the same time. This layer also looks for and fixes any transmission errors, ensuring that the data received matches the data sent.


The physical layer, which is the first and lowest layer, represents the network’s physical and electrical components, including cables and Bluetooth. The data transforms into signals at the physical layer and then appears as data on the receiving computer’s display after moving through the layers on the recipient’s end.

What is the presentation layer?

The Open Systems Interconnection (OSI) model’s presentation layer is the sixth layer. The OSI model is a concept used in computer networking that describes how data is transmitted from one computer to another. Each layer in the model is comprised of a set of protocols, or rules for data transmission, that enable the layer to carry out activities required for this transmission. Even computers or networks with various architectures or operating systems can experience this. Specifically, the presentation layer is in charge of translating data between layers and preserving data integrity.

Functions of the presentation layer

The operating system layer that resides on a computer is called the presentation layer. It interacts with the application layer and receives data entered by the user from there. Three crucial tasks are carried out by this layer in the transmission of data between computers. These are:


A collection of characters and numbers make up the data that the presentation layer receives from the application layer. Since different computers use different encoding schemes, the data must be converted to bit streams in order for the receiving computer to read it. The presentation layer at the sender’s end converts the data from a user-specific format to the standard binary format. The receiver’s presentation layer converts the data to a different, receiver-dependent format when it arrives there. This translation process guarantees that the data will display correctly for the recipient.

Encryption and decryption

Data must first be encrypted in order to make it unreadable to unauthorized parties. Data must then be decrypted in order to make it readable again. Both of these crucial security functions are carried out by the presentation layer because computers frequently handle sensitive data. Before entering the session layer, the layer encrypts the transmitting data at the sender’s end. The presentation layer decrypts the data on the receiver’s end so that the application layer can display it correctly.


Compression is the process of reducing data size. Smaller files transmit more quickly thanks to this process, which is beneficial for data transmission. Compression is carried out by the presentation layer on the sender’s end to reduce the bandwidth of the data being transmitted and speed up transmission. This procedure carried out by the presentation layer helps make sure that large data, such as multimedia files, reach their destination in the best possible time with no discernible quality loss.

Who can benefit from understanding the presentation layer?

Understanding the presentation layer and the other layers of the OSI model is beneficial for the majority of IT professionals and those working in industries adjacent to IT. They use the OSI model as a reference to develop products that integrate well with one another. The following are some examples of such professionals:

Network administrators

Network administrators may find it useful to comprehend the presentation layer when troubleshooting Consider a user in your organization who is unable to access a website, for instance. If this issue only affects you, you can assume that one of the host layers—those on the users end—is malfunctioning. If the issue persists across all web browsers, you can infer that the operating system’s presentation layer, rather than the application layer, is to blame. In light of this, you can fix the problem by modifying the system settings.

Cybersecurity professionals

Because security lapses at this level can compromise sensitive data transmitted over a network, understanding the presentation layer can be helpful. Encoding attacks, decryption downgrade attacks, and encryption attacks are common threats in the presentation layer. By ensuring that users install all security updates and patches, cybersecurity experts can help to increase security at this level.

Software vendors

Software providers ought to be able to explain how their products work. Therefore, vendors can specify which network components their software affects by understanding the presentation layer as well as the other layers of the OSI model. Additionally, it assists them in describing how their products relate to different network layers.


What is the example of presentation layer?

The presentation layer, which is located at Layer 6 of the Open Systems Interconnection (OSI) communications model, makes sure that communications passing through it are in the proper form for the recipient application. In other words, from the application layer’s perspective, it presents the data in a readable format.

What is presentation layer and session layer?

SSL, HTTP/HTML (agent), FTP (server), AppleTalk Filing Protocol, Telnet, and other examples of presentation layer protocols

Related Posts

Leave a Reply

Your email address will not be published. Required fields are marked *