What layer of the OSI model would you assume the problem is in if you typeshow interface serial 1and receive the following message?"Serial1 is down, line protocol is down."

Question

If you see that a serial interface and the protocol are both down, then you have a Physical layer problem. If you seeserial1 is up,line protocol is down, then you are not receiving (Data Link) keepalives from the remote end.

Accepted Answer

Answer

Physical layer

Answer

Data Link layer

Answer

Network layer

Answer

None. It is a router problem.

Question 944: What layer of the OSI model would you assume the problem is in if you typeshow interface serial 1and receive the following message?"Serial1 is down, line protocol is down."