SYSTEM FOR CALL FORWARDING FROM A FIRST COMMUNICATION NETWORK TO A SECOND REMOTE COMMUNICATION NETWORK AND A SYSTEM FOR VIRTUAL EXTENSION OF A MOBILE COMMUNICATION NETWORK BY AT LEAST A SECOND, REMOTE MOBILE COMMUNICATION NETWORK

摘要

The invention relates in a first main embodiment to a system for call forwarding from a first communication network to second remote communication network, wherein the second communication network is one of several mobile communication networks of the GSM type (Global System for Mobile Communications), which virtually extend the first communication network by all GSM mobile communication networks connected by roaming agreements. This is realized by providing a bridgehead in the first communication network which serves as a internetwork junction to one of the GSM networks (transition network), whereby calling numbers of the first communication network are assigned to the bridgehead to which further calling numbers of the first communication network are assignable by call forwarding. In the bridgehead occurs a conversion of the assigned numbers into GSM calling numbers, the bridgehead is connected via signaling channels and information channels to a Mobile Services Switching Center (MSC) of the transition network and also incorporates the basic services for subscribers of a GSM mobile communication network. A second main embodiment of the invention is related to a system for virtual extension of a mobile communication network by at least a second, remote mobile communication network, wherein one of communication network is of the GSM type, comprising a bridgehead between said first and second mobile communication network, said bridgehead serving as a internetwork junction to one of said mobile communication networks of the GSM type (transition network). said bridgehead acts as a Visitor Location Register for another mobile communication network and as a Home Location Register for the transition network, if a subscriber of said other mobile communication network is in the range of said mobile communication networks of the GSM type, and acts as a Home Location Register for said other mobile communication network and as a visitor Location Register for the transition network if a subscriber of said mobile communication networks of the GSM type is in the range of said other mobile communication network.