This standard establishes the technical requirements for interfacing and connecting a CMC switching system with an EC switched network. Compliance with these requirements is intended to assure minimum acceptable compatibility@ where compatible operation is the ability of an end use to establish@ maintain and disconnect a desired connection. The establishment of these connections may include the provision of paths through the EC network to provide access to or from ICs@ INCs (or consolidated carriers)@ other CMCs@ or other ECs. This standard does not specify all possible C-E interfaces@ e.g.@ common channel signaling@ network management@ and switched 56 kbps digital interfaces. In addition@ a few call-type protocols@ which are identified in the text and tables@ require further study before requirements can be defined.