This electrical-based DS3 line card complements Cisco's existing optical-based channelized OC-12 line card, now a network designer can select either an optical or electrical termination for DS3s into a Cisco 12000 backbone. In some cases, remote point-of-presence (POP) and customer installations can not get optical channelized service and the only high-speed service that is available is based on a traditional line DS3 service.The 6-port DS3 line card is an equivalent in functionality to the port adapter (PA-2T3) on the 7500, in that the DS3 line card can be used for either direct customer access or network-to-network connections.