567

Easy way to remember the OSI model (sh.itjust.works)

submitted 6 days ago by _thebrain_@sh.itjust.works to c/programmer_humor@programming.dev

44 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[-] slazer2au@lemmy.world 29 points 6 days ago

Easier way is to remember that the ISO model is defunked and you should use the TCP/IP model.

[-] BaroqueInMind@piefed.social 24 points 6 days ago

IP is layer 3 and TCP is layer 4.

Please elaborate your nonsensical comment.

[-] edinbruh@feddit.it 9 points 6 days ago* (last edited 6 days ago)

ISO/OSI is a neatly separated model mostly used on theory.

In practice, actual network stacks are often modeled after a simpler model that is called TCP/IP. Which despite the name is not actually TCP specific.

Here's the general description and correspondence to ISO/OSI:

Host to network / network access layer: it's mostly the nic and nic driver. It's sometimes numbered as 0 because some don't consider it part of the TCP/IP stack, but simply the nic driver. Corresponds to:
1. Physical
2. Datalink
Network layer: Corresponds to: 3. Network
Transport layer: Corresponds to: 4. Transport
Application layer: everything that's part of the application and not the network stack. Corresponds to: 5. Session 6. Presentation 7. Application

Or, you can just not care about how the actual software stack is separated, and continue to use the most complete model, knowing that everyone will understand what you when you say "layer 2/3/4" anyway.

Plus, some could say that the TCP/IP model is equally unfit because the Linux network subsystem doesn't care about layers.

Edit: I hope the formatting of that table isn't broken on your client, because it is on mine

load more comments (11 replies)

load more comments (19 replies)

this post was submitted on 22 Nov 2025

567 points (97.3% liked)