The purpose of this Recommendation is to define the BICC bearer control tunnelling protocol. The BICC bearer control tunnelling protocol is a generic tunnelling mechanism for the purpose of tunnelling Bearer Control Protocols (BCP) over the "horizontal" BICC interface between CCUs and the "vertical" CBC interface between CCU and BCU.This Recommendation defines the BICC bearer control tunnelling protocol, which transports the tunnelled protocol data units (PDU) of the bearer control protocols supported. It describes the coding and procedures for the identification of the tunnelled bearer control protocol. This Recommendation references the specific bearer control protocols that are tunnelled.