We at SOX (Serbian Open eXchange www.sox.rs) use a combination of Extreme
Networks Summit X650 (24x10G), and CISCO 4948E-E (4x10G+48xGEth), and
recently added Vyatta with 2xIntel 82599ES dual 10G NIC, built on HPDL180G6
with 2xE5620 Xeon, and for route servers we use 2 additional HP servers
Both Extreme, CISCO, and Vyatta could speak BGP, and do the routing, but we
prefer CISCO to do the routing, as well as aggregation of GEth customers,
VLAN translation etc.
Vyatta works like a charm, but in very limited rule, routing what CISCO
could not handle due to limitation in number of prefixes.
Routing in Extreme is very expensive due to high price of Core license which
is required for routing features.