Abstract: The present invention faces the issue of improving isolation of network slices in network slicing deployments where a centralized User Data Management, which includes subscription information for all users in a network with a plurality of network slices, is shared by the plurality of network slices. To solve this issue, the present invention provides for a distributed slice data repository for handling slice selection data for users equipped with a user equipment, UE, in a network that includes a plurality of network slices. This distributed slice data repository has: a slice user data repository, SDR, per network slice basis and including subscription information for each UE to be served by the network slice, and a slice selection repository, SSR, which is external to any network slice, shared by the plurality of network slices, and only includes slice selection data for every UE in the network.

Abstract: The present invention faces the issue of improving isolation of network slices in network slicing deployments where a centralized User Data Management, which includes subscription information for all users in a network with a plurality of network slices, is shared by the plurality of network slices. To solve this issue, the present invention provides for a distributed slice data repository for handling slice selection data for users equipped with a user equipment, UE, in a network that includes a plurality of network slices. This distributed slice data repository has: a slice user data repository, SDR, per network slice basis and including subscription information for each UE to be served by the network slice, and a slice selection repository, SSR, which is external to any network slice, shared by the plurality of network slices, and only includes slice selection data for every UE in the network.

Abstract: Methods and apparatus for implementing a Home Subscriber Server, HSS, (102, 200) a Serving Call Session Control Function, S-CSCF, (110, 300) and an Internet Protocol Multimedia Subsystem Application Server, IMS AS, (112, 400) in an Internet Protocol Multimedia Subsystem, IMS. The HSS comprises multi-subscription data for a user with a plurality of devices (100a, 100b, 100c). The multi-subscription data comprises a private identifier assigned for each of the plurality of devices and a common set of one or more public identifiers associated with each private identifier assigned for each of the plurality of devices. The S-CSCF transmits to the HSS a message for assigning a server in the IMS to a device. The HSS determines, based on a private identifier and multi-subscription data in the message, a multi-subscription indicator indicating whether the received private identifier is related to a multi-subscription. The HSS transmits a response to the received message comprising the multi-subscription indicator.