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New Member

prob with ospf and addressing

1) choose any two class "C" addresses

2)try to interconect 5 routers

3) the routers are routing with ospf

3)summerize at router one

write out the proc3ess for each router

router 1 connects to DMZ /27

router 2 has 64 hosts

router 3 has 128 hosts router 4 has32 hosts

New Member

Re: prob with ospf and addressing

It can be done, but very messy. If the question asked for 29, 61 and 125 hosts it would be fine, but to supply 32, 64 and 128 HOSTS means you would have to split the hosts onto more than one local logical network in order to support network, broadcast and gateway addresses for each network.......IF you are to stay within the single class C range given.

i.e. 25 bit network for most (125) of the router 3 hosts, 26 bit (61) for the router 2 network, 27 bit (29) for the router 4 network, at least 4 x 30 bit networks for the links between routers + some messy little secondary networks to make up the numbers on the routers 2,3 and 4.

As long as the routing protocol supports VLSM, with this limited information, it does not matter what the routing protocol is.

What is the origin of the question and is there any more information ?

New Member

Re: prob with ospf and addressing

APOLOGIES ! I will wake up and read the question...

The question said you are able to use TWO class C address ranges... so you have plenty of room.

24 bit for router 3 network, 25 bit for router 2, 26 bit for router 4, several 30 bit for the links and loads of room for loopbacks etc....

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