The 16-port OC-3 Packet over SONET/SDH (PoS) line cards are the next addition to the PoS-based products for the Cisco 12000 gigabit switch router (GSR) series, providing a cost-effective, high port density solution between GSRs and IP-related equipment such as edge routers and switches. The new line cards provide 16-port OC-3/PoS single-mode fiber interface using LC connectors.