Method and device for establishing an inter-radio frequency subsystem interface (ISSI) group call

A hosted inter-radio frequency subsystem interface (HIF) maintains a list of affiliated radio frequency subsystems (RFSSs), the list identifies at least one serving RFSS. An affiliation request is transmitted from the HIF to the home RFSS, which is a home RFSS of the group. The HIF receives from the serving RFSS a request to initiate an inter-RFSS group call to the group using HIF addressing. The HIF transmits a request to the home RFSS to initiate the inter-RFSS group call using serving RFSS addressing. A data packet from the home RFSS or the serving RFSS is received at the HIF. Upon receipt, the HIF transmits a copy of the data packet to the serving RFSS if the data packet was received from the home RFSS; otherwise, the HIF transmits a copy of the data packet to the home RFSS if the data packet was received from the serving RFSS.