Security key management in IMS-based multimedia broadcast and multicast services (MBMS)

摘要

A system, method, and nodes for managing shared security keys between a User Equipment, UE, an authentication node such as an SCF/NAF, and a service node such as a BM-SC or AS. The SCF/NAF allocates to each BM-SC, a different SCF/NAF identifier such as a fully qualified domain name, FQDN, from the FQDN space the SCF/NAF administers. The SCF/NAF then locally associates these allocated FQDNs with the connected BM-SCs and with different services. The network sends the correct FQDN to the UE in a service description for a desired service, and the UE is able to derive a security key using the FQDN. When the UE requests the desired service, the SCF/NAF is able to associate the service identifier with the correct FQDN and an associated BM-SC. The SCF/NAF uses the FQDN to obtain the security key from a bootstrapping server and sends it to the associated BM-SC. As a result, the UE and the associated BM-SC share a specific security key.