The Quad OC-12c/STM-4c POS line card provides Cisco 12000 series routers with four 622 Mbps POS interfaces on a single card. The card interfaces with the switch fabric in the Cisco 12000 series router and provides four OC-12c/STM-4c duplex SONET connections via SC connectors. Each connection is concatenated, which provides for increased efficiency by eliminating the need to partition the bandwidth.