Can 2 different wireless vendors systems be used side by side offering the same 802.1x authenticated SSID
Can different wireless vendors systems be used side by side offering the same 802.1x authenticated SSID?
Other vendors wireless gear
No you should never have mixed vendors wireless gear offering the same 802.1x SSID next to each other where a wireless user could simply roam directly between the AP's.
There is no ability for the 2 wireless systems to exchange this wireless users authenticated state.
Also if it is a B@EWC topology the ExtremeWireless controller always does arp proxy by default so if a user connects to one of our AP's and then roams to a Cisco we are going to keep the session active for the default 30 minutes and continue to tell the LAN this user is behind our controller for the next 30 minutes so packets will be forwarded the wrong way.