The 10-GE uplink card sends and receives a 10 GE 1310-nm signal to and from a 10-GE transponder module on a Cisco ONS. This card accepts up to four 2.5-Gbps (3.125-Gbps line rate) electrical signals from ESCON line cards and combines them into a 10-GE signal. The 10-GE uplink card has four separate redundant interfaces to the backplane. Each interface connects to the switch fabrics on the active and standby CPU switch modules.