<< How does the nortel IOS differ from the Cisco IOS? >>
Nortel doesn't use IOS, but I see what you're getting at. I have no clue on that one. Most Nortel stuff is configured with a little GUI interface, which, if I remember correctly, sets everything via SNMP sets and gets. Much like Ascend's high end switches. In fact the Ascend CBXs only allow you to set it's IP and gateway via the command line, everything else has to be done via their software (Naviscore I think it's called. I duuno, everything is Navi-something for those funky things).
I didn't even know Nortel offered certs. Doesn't surprise me though I guess. I think 3Com offers certs for their stuff as well know.