Jeremy’s IT Lab lecture video:
Day 12 - Life of a Packet
An extension to my previous note:
Day 11 - Routing Fundamentals (1)
Jeremy’s IT Lab lecture video:
Day 11 - Routing Fundamentals (1)
When a packet is being sent from router to router, the source/destination IP address stays the same. Meanwhile, the source/destination MAC address changes with each router hop.
Link to original
In the diagram below, PC1 is trying to send a packet to PC4.
- Before PC1 sends the packet, it checks the IP addresses and realizes that PC4 is located on a different subnet (PC1 is in 192.168.1.0/24, meanwhile PC4 is in 192.168.4.0/24), so that means that PC1 will send the packet to its own Default Gateway which is R1 in this case.
- From the diagram below, you can tell that the source MAC address is PC1’s address, and the destination MAC address is R1’s address. The source/destination MAC address will change with each hop from router to router until it finally reaches PC4.
