Nortel Networks Corporation

Northern Telecom Limited

Stephen Bird

Ricky Kumar Kaura

Kalyan K Basu

Hock Gan

Imran Rehman

Steven W Racz

Madhusudham Vudali

Alan Darbyshire

Robert Edward Lucas

David E Jones

Jaswant Virdee

A location register for a mobile communications network is coupled by an SS7 network for passing messages, has a mated location register at a different location to provide geographical redundancy, and has a status detector for detecting a status of the associated register, by sending a heartbeat message to the associated register. It deduces a fail if the message is returned by the signaling network. A cutover manager is arranged to enable a cutover on the basis of at least the detected status. By providing a more positive detection of a failure than merely passively interpreting a lack of response to the heartbeat, false triggering of cutovers owing to transient failures or temporary congestion, can be reduced. The cutover manager can verify the status by sending other messages by other routes, or using other criteria.

HLR mated-pair auto cutover

Typically data migration between HLR nodes is implemented by suspending operation of the HLR function in a mobile communications network while the data is transferred. This operation inevitably results in considerable network disruption. The present invention provides a method of on-line active data migration in which a subscriber diversion is implemented before subscriber data is sequentially transferred from one HLR node to another. The diversion redirects particular subscriber transactions from the second to the first HLR nodes if the subscriber has not been migrated from the first HLR node. The method allows the transfer to be implemented while the network HLR function remains on-line.

HLR data migration

An integrated MSC/HLR switch accommodates overloads by throttling peripherals during MSC overload conditions, and halting TCAP messages and throttling peripherals during HLR overload conditions.

Overload control for an integrated MSC/HLR switch

Growing community of inventors

Camberley, United Kingdom

Stephen Bird