The OSI Layer Model comprises seven layers, each representing an abstract concept used in network communication. Each layer is served by the layer below it. Through traversing the OSI model, data is divided into segments, then packets, then frames, and then finally into individual bits. The data travels from the top of the model to the bottom and then back to the top at the other end of the connection.
It is very important to be familiar with the OSI Model. Both for certifications, such as Network+ or CCNA and for the real world. Network engineers will often say they see a ‘Layer 2 problem’ or an issue on the ‘Network Layer’. You will look awfully silly if you do not know what they mean when they make such references. You should know and understand the different layers and which protocols live on which layer.
Place the seven layers of the OSI Model into their correct order by clicking on a layer’s name and then clicking on an empty box.
Presentation Layer
Data link Layer
Transport Layer
Application Layer
Session Layer
Network Layer
Physical Layer
Move to:
Layer 7
Layer 6
Layer 5
Layer 4
Layer 3
Layer 2
Layer 1
OSI Model Mnemonics
Pick whichever one you like best to help remember the order of the OSI layers:
- Please Do Not Throw Sausage Pizza Away
- All People Seem To Need Data Processing
- Please Do Not Teach Students Pointless Acronyms
- Please Do Not Take Sales People’s Advice
- Please Do Not Touch Superman’s Private Area
TCP/IP Model
The TCP/IP Model or Transmission Control Protocol /Internet Protocol suite serves the same function as the OSI Layer model, but is divided into four logical layers. Each of these four layers corresponds to one or more OSI Model layers. As above, practice memorizing the order of this model by ordering the layers from top to bottom.
Transport Layer
Network Access Layer
Internetwork Layer
Application Layer
Move to:
TCP/IP Model Mnemonic
This isn’t really an acronym, but you can use the girl’s name ‘Tina’ to remember the TCP/IP model layers:
A TINA
You can use our other interactive pages to check Ethernet RJ45 568A and 568B Wiring and the IP header format.
Download our Subnet Cheat Sheet for all the essential information you need to quickly perform subnet calculations in your head.If you want to learn more about networking and get the Cisco CCNA certification, we highly recommend the Cisco CCNA Gold Bootcamp as your CCNA training course. The CCNA is by far the most in-demand networking certification by employers, and the Gold Bootcamp is the highest rated Cisco course online. It has an average rating of 4.8 from over 30,000 public reviews:
