The present document defines the stage 2 specification of the Supplementary Service Barring of Incoming Calls (SS-BIC) for the Terrestrial Trunked Radio (TETRA) as provided by European operators. SS-BIC enables barring restrictions for incoming services, e.g. calls, to be set. SS-BIC specifies the definition, interrogation and operation of the supplementary service. The Switching and Management Infrastructure (SwMI) applies the SS-BIC definitions when an incoming service is requested for the restricted user. The SS-BIC actions are defined for the SwMI, for the Mobile Station (MS) and for the Line Station (LS). The SS-BIC information flows may be delivered over the Inter-System Interface (ISI).
