Cellular communications systems

摘要

In a mobile telephone network, a home location register (HLR) is provided with one or more cascaded home location registers to which some of the subscribers are allocated so as to share the workload in processing the subscriber information requests that are involved in the setting up of calls. Routing of requests to the correct HLR is simplified by routing all such requests to the original or master HLR and forwarding only those requests for which data is stored on one of the back-up or cascaded HLRs. This avoids the need for changes in the existing system routing plan. In a further embodiment two HLRs may form a mutually boosting pair.