Menu
Coddy logo textTech
START LEARNING
flag En iconEnglishdown icon

Recap - End to End

Lesson 32 of 32 in Coddy's The OSI Model course.

challenge icon

Challenge

Medium

The whole course in four questions. Print, one answer per line:

  1. The layer number where routing decisions happen
  2. The PDU that actually crosses the physical wire (lowercase)
  3. The header that carries port numbers (uppercase)
  4. The protocol that turns names into addresses (uppercase)

Expected output:

3
bits
TCP
DNS

Try it yourself

Terminal

All lessons in The OSI Model

1Why Layers

The Layering IdeaSeven LayersNumbers and NamesRecap - The Stack

4The Network Layer

IP and TTLPing and ICMPRouting TablesRecap - Layer Three

7Encapsulation

Wrapping DataHeaders EverywhereReading a CaptureRecap - Follow the Wrap

2The Physical Layer

Bits on a WireHow Long Will It TakeDuplex and Collisions

5Transport: TCP and UDP

PortsThe TCP HandshakeTCP vs UDPSockets in ActionRecap - Layer Four

8The Journey of a Packet

A Click HappensCrossing the NetworksArriving and ClimbingRecap - End to End

3Data Link and MACs

Frames and MACsReading a MACARPRecap - Layer Two

6The Upper Layers

Session and PresentationThe Application LayerWatching the LayersRecap - Top of the Stack

Practice on your own: Terminal playground