Cisco The Upper OSI Layers

In this Cisco CCNA tutorial, you’ll learn about the upper layers of the OSI model. That’s the upper three layers, 5, 6, and 7. Scroll down for the video and also the text tutorials.

Cisco The Upper OSI Layers Video Tutorial

YouTube video

Zander Claassen

Zander Claassen

This course from Neil is by far one of the best courses (online or classroom) that I ever done. Not only does he explain the information really well but he also provides you with the opportunity to try the stuff that you’ve learned in a real world environment.
This is what really set this course apart, I think most people will agree that you only really learn and remember information when you do the process yourself.
He was also kind enough to give me some really good career advice.
I would highly recommend this course to anyone interested in CCNA certification.

Zander Claassen

 

Network engineers don't typically work directly with those upper three layers of the OSI model. They're more relevant to application developers, but we still need to know what they do. And for the exam, we need to know the definitions of each of the layers as well. It's quite likely that you'll be tested on that.

 

Cisco The Upper OSI Layers

 

In this tutorial, I will be giving you the Cisco definitions, so you'll be ready for the exam. The information included in the upper layers would include the Message Body and the Subject Line in an email message, for example.

 

Layer 7 – The Application Layer

 

So let's look at the three top layers starting with Layer 7, the Application Layer. This provides network services to the applications of the end user. It differs from the other layers in that it does not provide services to any other OSI layer.

 

The Application Layer establishes the availability of intended communication partners. Intended communication partners would be the host that this host is communicating with.

 

So the Application Layer establishes the availability of intended communication partners, not just a straight line going to the other host. It then synchronizes and establishes agreement on procedures for error recovery and control of data integrity. Data integrity means checking that data has not been altered or corrupted in transit.

 

 

Layer 6 – The Presentation Layer

 

The next layer is Layer 6, the Presentation Layer. This ensures that the information that is sent at the Application Layer of one system is readable by the Application Layer of another system.

 

The Presentation Layer can translate among multiple data formats using a common format. For example, it might need to do this for computers with different encoding schemes.

 

 

Layer 5 – The Session Layer

 

The last layer of our upper layers is Layer 5, the Session Layer. This establishes, manages, and terminates sessions between two communicating hosts. The Session Layer also synchronizes dialogue between the Presentation Layer of the two hosts and manages data exchange.

 

For example, we might have web servers that have got many users that are using that web server. So, in that case, we would have multiple incoming sessions.

 

The Session Layer keeps track of all of those. It also offers efficient data transfer, Class of Service (CoS), which is similar to efficient data transfer, and exception reporting of upper layer problems.

 

Additional Resources

 

The TCP/IP and OSI Networking Models: https://www.ciscopress.com/articles/article.asp?p=1757634&seqNum=2

Introduction to the OSI Model: https://networklessons.com/cisco/ccna-routing-switching-icnd1-100-105/introduction-to-the-osi-model

Cisco Open Systems Interconnection OSI Model Overview: https://www.flackbox.com/cisco-open-systems-interconnection-osi-model-overview

 

Want to practice Cisco CCNA technologies on your laptop? Download my complete 350-page Cisco CCNA Lab Guide for free.

 

Click Here to get my Cisco CCNA Gold Bootcamp, the highest rated CCNA course online with a 4.8 star rating from over 20,000 public reviews.

Libby Teofilo

Text by Libby Teofilo, Technical Writer at www.flackbox.com

With a mission to spread network awareness through writing, Libby consistently immerses herself into the unrelenting process of knowledge acquisition and dissemination. If not engrossed in technology, you might see her with a book in one hand and a coffee in the other.