The CIP2 provides up to two channel interfaces for Cisco 7000 series and Cisco 7500 series routers; in some situations, this can eliminate the need for a separate front-end processor (FEP). The CIP2 contains combinations of a bus and tag (also called an original equipment manufacturer's interface [OEMI] and a parallel I/O interface) adapter and an Enterprise Systems Connection (ESCON) adapter. The bus and tag adapter is called the Parallel Channel Adapter (PCA), and the ESCON adapter is called the ESCON Channel Adapter (ECA). The PCA and ECA connect directly to the CIP2, and all combinations of the two adapters are available.