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New Member

Two routers named Atlanta and Brevard

i Assume there is an issue with BW mismatch. but the answer given as IP mismacth. which one is corect.

Two routers named Atlanta and Brevard are connected by their serial interfaces as shown in the exhibit, but there is no data connectivity between them. The Atlanta router is known to have a correct configuration. Given the partial configurations shown in the exhibit, what is the problem on the Brevard router that is causing the lack of connectivity?

A. A loopback is not set

B. The IP address is incorrect.

C. The subnet mask is incorrect.

D. The serial line encapsulations are incompatible.

E. The maximum transmission unit (MTU) size is too large.

F. The bandwidth setting is incompatible with the connected interface.


Please see the attached image

Hall of Fame Super Gold

Two routers named Atlanta and Brevard


New Member

Two routers named Atlanta and Brevard

hi Leo,

canu pls explain. since i have read somewhere that BW mismatch is also one of the problems for conectivity.

Hall of Fame Super Gold

Two routers named Atlanta and Brevard

Geez.  Serial interface ...

If I rememebered correctly, BW statement is used for network monitoring or computing by routing protocols (such as OSPF).

This is Serial Interface, and if memory serves me correct, it's a point-to-point connection.

If it's point-to-point connnection, why are the subnet discontiguous?  Should they be in the same subnet?

Super Bronze

Re: Two routers named Atlanta and Brevard


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The problem is, the two interfaces have interfaces in different subnets.

I agree with Leo, the likely answer is "B", but it could also be "C".  (I.e. changing either just one device's IP or both devices' mask would correct the problem.  Possible configurations for the two routers might be: and; and; and


To your later question about bandwidths, a mismatch may be a problem if the BW is from clock rates.  If from bandwidth statements, answer "F", it doesn't matter.