The HIP provides a single HSSI, EIA/TIA-612/613 network interface for Cisco 7000 series and Cisco 7500 series routers. The HIP provides a single, full-duplex HSSI for transmitting and receiving data at rates of up to 52 megabits per second (Mbps).HSSI, which was recently standardized as EIA/TIA-612/613, provides access to services at T3 (45 Mbps), E3 (34 Mbps), and Synchronous Optical Network (SONET) STS-1 (51.82 Mbps) rates. The actual rate of the interface depends on the external data service unit (DSU) and the type of service to which it is connected. The HIP supports both 16- and 32-bit cyclic redundancy checks (CRCs). The default is 16-bit CRCs. To enable 32-bit CRCs, you must use a configuration command, depending on the hardware version of your HIP.