Cisco were an early player in the router game.
They concentrated on mid to top range routers used by ISP for inter ISP
links.
The current top end 12000 series routers, support OC-3 {155Mbps}, OC-12
{622Mbps} SONET inter router links or OC-12 ATM feeds. Up to a maximum
aggregate rate of 2.4Gbps.