Internet2 (i2) is was initiated by the a bunch of Universities (now run by UCAID). Internet 2 differs in that it is a private network for research only, mostly academic but open also to commercial research. March 1999: Internet 2 network included some 200 universities in the US.
Difference in Internet2 from Internet1, other then the fact that it is a entirely seperate network, is its implimentatin of QoS and CoS in Internet 2.