Define Network in routing protocol

[Eli G.]

Hi guys.

I'm studding for CCNA and im at the routing protocols now.

When define which routing protocol i want to use (RIP EIGRP etc), i need to define a network. The router then publish the whole subnet. lets say i have an INT with IP 192.168.1.1/30 so in running config i will see that it publish 192.168.1.0 (as if its class c).

but then i learned that if you want it to publish the exact network i can add 0.0.0.0 at the end of the command (like: network 192.168.1.1 0.0.0.0).

now in running-config i will see that eigrp network is 192.168.1.1 0.0.0.0 AND 192.168.1.1

my question is why is it 0.0.0.0 and not 255.255.255.255

Thanks for your help.

[Seb Rupik · Accepted solution]

Hi there,

It is a wildcard mask:

https://en.wikipedia.org/wiki/Wildcard_mask

cheers,

Seb.

[Eli G.]

Thanks Seb. the wiki explained it perfectly.
Thanks for your time.

Cheers :)

[Reza Sharifi]

Hi,

192.168.1.1 0.0.0.0 

This is the smallest address.

If you try 192.168.1.1 255.255.255.255 in EIGRP or OSPF

They both will still show you 192.168.1.1 0.0.0.0 

HTH