What port address of the router must respond over time in order to live in a crowded message?

Question

Given the following situation:

PC --- |aa  RTR1  bb| --- |aa  RTR2  bb| --- |aa  RTR3  bb| etc  

Each of them is |aa rtr bb|intended for a router with two ports aaand bb.

When I make a trace route from my PC, what port address of the router must respond over time in order to live exceeded in the transit message?

I seem to remember that I was taught to think that the router is in as many parts as the ports, so in my scenario, when it aaforwards the packet to bband reduces the TTL to 0, this will be the port address aain the error message. I am trying to find the final answer.

Answer 1

Since each router sends you an ICMP packet using aaand does not use bb, the packet sent will have an aaaddress, not bb.

The router generates an ICMP packet and sends it to you. A source address that is in the package is the source address from which the packet is sent, aa.