Refer to the exhibit. In this VLSM addressing scheme, what summary address would be sent from router A?
A.
172.16.0.0 /16
B.
172.16.0.0 /20
C.
172.16.0.0 /24
D.
172.32.0.0 /16
E.
172.32.0.0 /17
F.
172.64.0.0 /16
In this VLSM addressing scheme, what summary address would be sent from router A?
Refer to the exhibit. In this VLSM addressing scheme, what summary address would be sent from router A?
Explanation
Router A receives 3 subnets: 172.16.64.0/18, 172.16.32.0/24 and 172.16.128.0/18.
All these 3 subnets have the same form of 172.16.x.x so our summarized subnet must be also in that form -> Only A, B or C is correct.
The smallest subnet mask of these 3 subnets is /18 so our summarized subnet must also have its subnet mask equal or smaller than /18.
-> Only answer A has these 2 conditions -> A is correct.
This is the end for VLSM, Classful & Classless routing.
The topic of route summarisation shall be covered in another post.
no B is correct