Cisco SPA-1CHOC3-CE-ATM= network switch module

1-Port Channelized OC-3/STM-1 Circuit Emulation and ATM SPA, Spare The Cisco 1-port Channelized OC3/STM-1 circuit emulation over packet and ATM SPA is available on high-end Cisco routing platforms offering the benefits of network scalability with lower initial costs and ease of upgrades. The Cisco SPA/SIP portfolio continues the Cisco focus on investment protection along with consistent feature support, broad interface availability, and the latest technology. The Cisco SPA/SIP portfolio allows different interfaces (Packet over SONET/SDH [POS], ATM, Ethernet, and so on) to be deployed on the same interface processor.

The Circuit Emulation over Packet (CEoP) SPAs provide a new service offering. These SPAs provide bit-transparent data transport that is completely protocol independent.
For the first time, this allows network administrators to use their existing IP/MPLS network to provide leased-line emulation services or to carry data streams or protocols that do not meet the format requirements of other multiservice platform interfaces. In addition, these SPAs can be used for low-speed ATM services, including Inverse Multiplexing over ATM (IMA).