I know when redistributing between classless and classful boundaries, you need to summarize the classless networks before the router you using for redistribution. This would be easy to do if you had networks such as 172.16.4.0, 172.16.8.0, 172.16.128.0, as you could summarize them all into the classful network address of 172.16.0.0 255.255.0.0. What do you do though when you have networks such as 210.100.1.0, 210.100.2.0, 210.100.3.0. Normally, the summary addess for this would be 210.100.0.0 255.255.252.0. This isnt a Classful address though because of the SM. You can't do 210.100.0.0 255.255.255.0 (this would exclude those individual networks), 210.100.0.0 255.255.0.0 (classful C networks have a SM of 255.255.255.0). Anyone have an idea of how I would summarize these into a classful address so I would be able to redistribute into a classful network?