The new, enhanced CHOC12/STM4 card is designed to simplify the deployment of DS3/E3 and OC3c/STM1 services by providing up to 12 DS3/E3 channels over a single optical interface. In SONET mode, the card can be configured to support any combination of DS3/E3, subrate DS3, and OC3c. In SDH mode, the card can support E3/DS3 and STM1s. The card also comes with four Gigabit Ethernet interfaces that enable additional connectivity into server farms or service provider networks.