Hmm not heard of running the stack with different images, if this is possible then it could be a bad thing as stated if the switch with the advanced IOS fails it reverts back to the basic IOS and you loose the features associated with it.
Hi carlI assume that you don't want to change your existing STP configuration to accommodate these switches so your simplest solution is going to be layer 3 interfaces between the cisco and nortel switches if the nortel can do this of course.
Mahmoodthe summary address 192.168.0.0 255.255.248.0 does encompass all the subnets, it will advertise all addresses from 192.168.0.0 to 192.168.7.255. However 192.168.4.0/24 is not one of the ranges that are in the summary. Routing table outputC ...