VLSM question

Hi,

I'm preparing for my CCNA ... I cam across a question on book that I wasn't sure if I got it right.

Question : Given network 10.10.4.0/22
R1 fa0/0 – 100 hosts
R2 fa0/0 – 200 hosts
R2 fa0/1 – 50 hosts

Assign network addresses efficiently – ie so that the routers can be configured to the fewest number of routes in their routing tables. Write the network addresses into the diagram below.

MY ANSWER :
R1 fa0/0 – 100 hosts - 10.10.4.0/25
R2 fa0/0 – 200 hosts - 10.10.5.0/24
R2 fa0/1 – 50 hosts - 10.10.6.0/26
btw routers – 2 hosts - 10.10.6.64/30

I was wondering if my IP addressing will result in the fewest number of routes or is there a better solution ?

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Comments

RouteMyPacket

Ok, so we don't even need a /22 for this IP design but with it we have

10.10.4.0 - 10.10.7.0

Always start with the largest network first so

R2 F0/0 - 200 Hosts

10.10.4.0/24

R1 F0/0 - 100 Hosts

10.10.5.0/25

R2 F0/1 - 50 Hosts

10.10.5.128/26

Serial Link between Routers

10.10.5.192/30

You are going to have "4" networks no matter what you do. The deal is subnet it out so that the routing table has the least amount of routes right? I mean if you are using EIGRP, then

router eigrp 100
network 10.10.0.0

The thing is, to really answer your own question. Fire up GNS3 and create this topology, what does the routing table look like?

My thoughts above would make your routing table look like this

R1

10.0.0.0/8 is variably subnetted, 4 subnets, 4 masks
D 10.10.4.0/24 [90/2172416] via 10.10.5.194, 00:00:23, Serial1/0
C 10.10.5.0/25 is directly connected, FastEthernet0/0
D 10.10.5.128/26 [90/2172416] via 10.10.5.194, 00:00:23, Serial1/0
C 10.10.5.192/30 is directly connected, Serial1/0

R2

10.0.0.0/8 is variably subnetted, 4 subnets, 4 masks
C 10.10.4.0/24 is directly connected, FastEthernet0/0
D 10.10.5.0/25 [90/2172416] via 10.10.5.193, 00:01:10, Serial1/0
C 10.10.5.128/26 is directly connected, FastEthernet0/1
C 10.10.5.192/30 is directly connected, Serial1/0

What would yours look like?

theodoxa

R2 Fa0/0 – 10.10.4.0/24
R2 Fa0/1 – 10.10.5.0/24
SUMMARY ADDRESS placed on R2's Serial Port - 10.10.4.0/23
Serial Link - 10.10.7.252/30 (I used the last possible subnet so that you could add more subnets in between if need be.)
R1 fa0/0 – 10.10.6.0/25

chelseaCA

OK, thanks guy