Definition and function: Call Control Signaling like setting up a call, tear down, negotiation of parameters Provides signaling independent of bearer technology and signal transport technology BICC is Adaptation of ISUP as defined in the scope of Recommendation Q.1901 series
CSF: Call Service Function, performs call control BCF: Bearer Control Function, performs bearer control function SN: CSF with associated BCF CMN: CSF without any BCF associated