Basic call state model
In Intelligent Network and CAMEL switching, a BCSM is a Basic Call State Model. A fundamental concept for IN control is the basic call state model (BCSM). When a call is processed Types. by an exchange, the call goes through a number of pre-defined phases. These phases of the call are described in the BCSM. The BCSM generally follows the ISUP signalling of a call State machine description. In the following IN BCSMs, bold Detection Points and Points In Call are also present in the CAMEL Ph1 subset. TODO: Expand to Ph2,3,4 Basic call state