eq(...) Call-handling connectRef(...) Call-handling ESM in LE callStateRep(...) ESM in TE connectCnf(...) LE resources TE resources LSM abstract protocol specification Operation is release Behavior is: Operation is callState "When detecting a connectRequest, the LE-ESM shall report (...) check that the service requested matches with the serv- Operation is connect ices subscribed by the caller (the TE-ESM)." request (...) confirm (...) "If the caller accepts any channel, the network selects refuse (...) an available channel associated with the caller." "When the connectRequest is accepted, the LE machine generates a callStateReport(inProgress) to the caller." "When the call is established to the callee, the LE machine shall generate a connectConfirm to the caller. Parameter definitions, examples: connectRequest(call TYPE, service TYPE, caller TYPE, callee TYPE, channel TYPE, ...) connectConfirm(call TYPE, callState(inCall(1)) TYPE) callStateReport(call TYPE, callState{inProgress (2)} TYPE) Fig. 2.25 The abstract protocol is described by an AMLs model (an abstract-machine system), a number of operation specifications, and a behavior specification (textual here, or graphical as a state diagram) The abstract protocol specification consists of, besides the model, a number of operation specifications and a behavior specification: 2 Layer Structures Each operation specification defines one or several ASPs and their parameters. Each parameter has a name (that is not necessarily the same as the correspond- ing message-parameter names) and a value range. It also has a type designation which defines how it shall be encoded in messages. Different type and encoding systems may be used, e.g. ASN.1 ("abstract syntax notation no 1") and BER ("basic encoding rules"). You can read more about operation specifications in Muth (2001). The behavior specification in Fig. 2.25 is extracted by textual fragments from the DSS1 L3 standard. It is also transcribed SO that it refers ASPs and ASP parameters instead of messages and message para