Recovery procedures between subscriber registers in a telecommunications network

Abstract

The present invention is aimed to provide subscriber registers of a mobile network with higher performance and memory capacity whilst keeping recovery procedures, such as redundancy and restoration procedures, up to reasonable levels and measurements of network performance, signalling load and response time. The present invention provides for a new clustered architecture for subscriber registers, wherein each subscriber register comprises a number of processing blades, each processing blade handling a reduced number of subscribers, and wherein more processing blades can be added without affecting other components in the subscriber register. Failures and unavailability are expected to often occur on a processing blade basis, so that recovery procedures may be carried out for a reduced number of subscribers, thus being completed with lower signalling load and response times. To this end, the present invention also provides for a new method of updating subscriber data between two subscriber registers where at least one follows the clustered architecture.

1 . A clustered subscriber register holding subscriber data for subscribers in a mobile network, the subscriber data comprising subscription data and location data for each subscriber, the clustered subscriber register comprising:
 an input unit arranged for receiving location data for a subscriber from a seizing node in the mobile network;   a plurality of processing blades, each processing blade handling a number of subscribers and comprising:
 a storage arranged for storing subscriber data for the subscriber, and a processor arranged for processing a course of actions to be taken for the subscriber depending on subscriber data for the subscriber; 
   a distributor for determining the processing blade currently handling the subscriber; and   an output unit arranged for submitting a subscriber identity for the subscriber, an identifier of the clustered subscriber register and an identifier of the processing blade handling the subscriber towards a secondary subscriber register in the mobile network, wherein   the input unit is arranged for receiving from the secondary subscriber register an upgraded operation to process a course of actions for the subscriber, the upgraded operation including the subscriber identity for the subscriber and the identifier of the processing blade handling the subscriber.   
     
     
         2 . The clustered subscriber register of  claim 1 , wherein the output unit is arranged for submitting, along with the subscriber identity for the subscriber, the identifier of the clustered subscriber register and the identifier of the processing blade, a set of subscriber data for the subscriber towards the secondary subscriber register in the mobile network. 
     
     
         3 . The clustered subscriber register of  claim 1 , acting as a Visitor Location Register (VLR) holding subscriber data for subscribers roaming in a VLR area of the mobile network, the input unit being arranged for receiving location data for the subscriber from a Mobile Switching Centre (MSC) currently serving the subscriber, the output unit being arranged for submitting to a Home Location Register (HLR) which holds subscriber data for subscribers of the mobile network, the subscriber identity for the subscriber, the identifier of the Visitor Location Register and the identifier of the processing blade handling the subscriber therein. 
     
     
         4 . The clustered subscriber register of  claim 2 , acting as a Home Location Register (HLR) holding subscriber data for subscribers of the mobile network, the input unit being arranged for receiving location data for the subscriber from a Visitor Location Register (VLR), which is serving the subscriber and holds subscriber data for subscribers roaming in a VLR area of the mobile network, the output unit being arranged for submitting to a redundant Home Location Register (R-HLR), which holds redundant subscriber data for subscribers of the mobile network, the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Location Register and the identifier of the processing blade handling the subscriber therein. 
     
     
         5 . The clustered subscriber register of  claim 4 , further comprising a replicator for coordinating with the redundant Home Location Register a redundancy procedure for sending subscriber data for subscribers handled in a processing blade identified by a given identifier. 
     
     
         6 . The clustered subscriber register of  claim 5 , wherein the replicator further comprises a state-transition machine operating on a processing blade basis to determine the status of the redundancy procedure on course for each processing blade. 
     
     
         7 . The clustered subscriber register of  claim 2 , acting as a Home Location Register holding subscriber data for subscribers of the mobile network, the input unit being arranged for receiving location data for the subscriber from a Visitor Location Register, winch is serving the subscriber and holds subscriber data for subscribers roaming in a VLR area of the mobile network, the output unit being arranged for submitting to the Visitor Location Register the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Location Register and the identifier of the processing blade handling the subscriber therein. 
     
     
         8 . The clustered subscriber register or  claim 2 , acting as a Home Subscriber Server (HSS) holding subscriber data for subscribers of an IP Multimedia Subsystem (IMS) in the mobile network, the input unit being arranged for receiving location data for the subscriber from a Serving Call Session Control Function server (S-CSCF), which is assigned for serving the subscriber in the IMS, and the output unit being arranged for submitting to said Serving Call Session Control Function server the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Subscriber Server and the identifier of the processing blade handling the subscriber. 
     
     
         9 . The clustered subscriber register of  claim 7 , further comprising a restorer arranged for submitting, after having recovered from a failure affecting a processing blade, a reset indication to secondary subscriber registers holding subscriber data for those subscribers handled by the recovered blade, the reset indication including the identifier of the clustered subscriber register and the identifier of the recovered processing blade. 
     
     
         10 . A secondary subscriber register arranged for holding subscriber data for subscribers in a mobile network, the subscriber data comprising subscription data and location data for each subscriber, the secondary subscriber register comprising:
 an input unit arranged for receiving from a clustered subscriber register, which holds subscriber data her a subscriber in the mobile network, a subscriber identity for the subscriber, an identifier of the clustered subscriber register, and an identifier of a processing blade handling the subscriber at the clustered subscriber register;   a storage arranged for storing subscriber data, the subscriber identity, the identifier of the clustered subscriber register and the identifier of the processing blade for the subscriber;   a processor arranged for processing a course of actions to be taken for the subscriber depending on the received subscriber data; and   an output unit arranged for submitting towards the clustered subscriber register an upgraded operation to process a course of actions tor the subscriber, the upgraded operation including the subscriber identity for the subscriber and the identifier of the processing blade handling the subscriber.   
     
     
         11 . The secondary subscriber register of  claim 10 , wherein the input unit is arranged for receiving a set of subscriber data for the subscriber, along with the subscriber identity for the subscriber, the identifier of the clustered subscriber register and the identifier of the processing blade, from the clustered subscriber register in the mobile network. 
     
     
         12 . The secondary subscriber register of  claim 10 , acting as a Home Location Register (HLR) holding subscriber data for subscribers of the mobile network, the input unit being arranged for receiving from a Visitor Location Register (VLR), which is currently serving the subscriber and holds subscriber data for subscribers roaming in a VLR area of the mobile network, the subscriber identity for the subscriber, the identifier of the Visitor Location Register and the identifier of the processing blade handling the subscriber. 
     
     
         13 . The secondary subscriber register of  claim 11 , acting as a redundant Home Location Register (R-HLR) holding redundant subscriber data for subscribers of the mobile network, the input unit being arranged for receiving from a clustered Home Location Register, which holds subscriber data for subscribers of the mobile network, the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Location Register and the identifier of the processing blade handling the subscriber. 
     
     
         14 . The secondary subscriber register of  claim 13 , further comprising a replicator for coordinating with the clustered Home Location Register a redundancy procedure for receiving subscriber data for those subscribers handled in a processing blade identified by a given identifier. 
     
     
         15 . The secondary subscriber register of  claim 14 , wherein the replicator further comprises a state-transition machine operating on a processing blade basis to determine the status of the redundancy procedure on course for each processing blade. 
     
     
         16 . The secondary subscriber register of  claim 11 , acting as a Visitor Location Register currently serving the subscriber and holding subscriber data for subscribers roaming in a VLR area of the mobile network, further comprising an output unit arranged for submitting location data for the subscriber towards a Home Location Register, which holds subscriber data for subscribers of the mobile network, and wherein the input unit is arranged for receiving from the Home Location Register the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Location Register and the identifier of the processing blade handling the subscriber. 
     
     
         17 . The secondary subscriber register of  claim 11 , acting as a Serving Call Session Control Function server (S-CSCF) serving the subscriber in an IP Multimedia Subsystem (IMS) of the mobile network, further comprising an output unit arranged for submitting location data for the subscriber towards a Home Subscriber Server (HSS), which holds subscriber data for subscribers of IMS in the mobile network, and the input unit being arranged for receiving from the HSS the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Subscriber Server and the identifier of the processing blade handling the subscriber. 
     
     
         18 . The secondary subscriber register of  claim 16 , further comprising a restorer arranged for receiving a reset indication from the clustered subscriber register, the reset indication including the identifier of the clustered subscriber register and an identifier of a processing blade recovered after failure; and arranged for initiating a restoration procedure for ail the subscribers in the secondary subscriber register with the received identifier of a processing blade. 
     
     
         19 . A method of updating subscriber data between a clustered subscriber register and a secondary subscriber register, both holding subscriber data for subscribers in a mobile network, the subscriber data comprising subscription data and location data, the method comprising the steps of:
 receiving at the clustered subscriber register location data for a subscriber from a serving node in the mobile network;   determining at a distributor of the clustered subscriber register a processing blade currently handling the subscriber among a plurality of processing blades, each processing blade handling a number of subscribers and including a storage and a processor;   processing at the processor included in the processing blade, a course of actions to be taken for the subscriber depending on the subscriber data;   submitting from the clustered subscriber register towards the secondary subscriber register a subscriber identity for the subscriber, an identifier of the clustered subscriber register, and an identifier of the processing blade handling the subscriber at the clustered subscriber register; and   receiving at the clustered subscriber register from the secondary subscriber register an ungraded operation to process a course of actions for the subscriber, the upgraded operation including the subscriber identity for the subscriber and the identifier of the processing blade handling the subscriber.   
     
     
         20 . The method of  claim 19 , wherein the step of submitting from the clustered subscriber register towards the secondary subscriber register a subscriber identity for the subscriber, an identifier of the clustered subscriber register, and an identifier of the processing blade includes a step of obtaining from the storage in the processing blade a set of subscriber data far the subscriber, and a step of submitting the set of subscriber data for the subscriber. 
     
     
         21 . The method of  claim 19 , wherein the step of receiving location data for the subscriber takes place at a Visitor Location Register (VLR) holding subscriber data for subscribers roaming in a VLR area of the mobile network, the location data for the subscriber being submitted from a Mobile Switching Centre (MSC) currently serving the subscriber, and wherein the step of submitting takes place at the Visitor Location Register towards a Home Location Register (HLR), which holds subscriber data for subscribers of the mobile network, the submission including the subscriber identity for the subscriber, the identifier of the Visitor Location Register and the identifier of the processing blade handling the subscriber therein. 
     
     
         22 . The method of  claim 20 , wherein the step of receiving location data for the subscriber takes place at a HLR holding subscriber data for subscribers of the mobile network, the location data for the subscriber being submitted from a Visitor Location Register, which is serving the subscriber and holding subscriber data for subscribers roaming in a VLR area of the mobile network, the step of submitting taking place at the HLR towards a redundant Home Location Register (R-HLR), which holds redundant subscriber data for subscribers of the mobile network, the submission including the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Location Register and the identifier of the processing blade handling the subscriber therein. 
     
     
         23 . The method of  claim 22 , further comprising a step of coordinating between the Home Location Register and the R-HLR a redundancy procedure for sending subscriber data for those subscribers handled in a processing blade identified by a given identifier. 
     
     
         24 . The method of  claim 22 , further comprising a step of operating a state-transition machine on a processing blade basis to determine the status of the redundancy procedure on course for each processing blade. 
     
     
         25 . The method of  claim 20 , wherein the step of receiving location data for the subscriber takes place at a Home Location Register holding subscriber data for subscribers of the mobile network, the location data for the subscriber being submitted from a Visitor Location Register, which is serving the subscriber and holding subscriber data for subscribers roaming in a VLR area of the mobile network, the step of submitting taking place at the HLR towards the Visitor Location Register, the submission including the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Location Register and the identifier of the processing blade handling the subscriber therein. 
     
     
         26 . The method of  claim 20 , wherein the step of receiving location data for the subscriber takes place at a Home Subscriber Server (HSS) holding subscriber data for subscribers of an IP Multimedia Subsystem (IMS) in the mobile network, the location data for the subscriber being submitted from a Serving Call Session Control Function server (S-CSCF), winch is assigned for serving the subscriber in the IMS, the step of submitting taking place at the Home Subscriber Server towards said Serving Call Session Control Function server, the submission including the subscriber identity and the set of subscriber data for the subscriber, the identifier of the Home Subscriber Server and the identifier of the processing blade handling the subscriber therein. 
     
     
         27 . The method of  claim 25 , further comprising a step of submitting, after having recovered from a failure affecting a processing blade, a reset indication from the Home Location Register to those Visitor Location Registers holding subscriber data for those subscribers handled by the recovered blade, the reset indication including the identifier of the Home Location Register and the identifier of the recovered processing blade. 
     
     
         28 . The method of  claim 26 , further comprising a step of submitting, after having recovered from a failure affecting a processing blade, a reset indication from the Home Subscriber Server towards those Serving Call Session Control Function servers holding subscriber data for those subscribers handled by the recovered blade, the reset indication including the identifier of the Home Subscriber Server and the identifier of the recovered processing blade.