This Recommendation describes the protocol for access networks that support Bearer Independent Call Control (BICC). It defines the access network protocol in terms of formats, codes, and procedures. The protocol defined by this Recommendation is to be used between "Access Concentration Nodes" and "Interface Serving Nodes" or "Interface Mediation Nodes". This protocol is called the BICC Access Network protocol. It includes three signalling associations: Call Control; Access Network Control; Remote Media Control. Other protocols, not specified by this Recommendation, are used between Access Concentration Nodes and Serving Nodes for the control of bearers. Other protocols, also not specified in this Recommendation, are used between bearer control functions and other access network functions across the vertical associations. The scope of this Recommendation is illustrated by the highlighted oval in Figure 1.