auto-summarization: classful vs classless routing protocols
- by yorble
Suppose a router R1 is directly connected to the following subnets:
10.1.0.0/24
10.1.1.0/24
10.1.2.0/24
10.1.3.0/24
If it is running RIPv1, it will advertise:
"i have the network 10.0.0.0" (implicitly understood by receiving RIPv1 routers as 10.0.0.0/8 because the protocol is classful)
but suppose we changed the routing protocol to RIPv2 and turned ON auto-summarization.
Would it behave in the same way? Would it advertise:
"i have the network 10.0.0.0" (advertised WITHOUT subnet mask, and implicitly understood by other routers as 10.0.0.0/8)
OR would it auto-summarize in a non classful way like:
"i have 10.1.0.0/22" (advertised as network id and subnet mask pair)
In other words, does turning on auto-summarization in RIPv2 (or other classless routing protocols) cause it to auto-summarize in a classful manner or simply auto-summarize classlessly to the best of its ability?