During a registration procedure by a User Equipment (UE) via a Proxy Call Session Control Function (P-CSCF) node and a Serving Call Session Control Function (S-CSCF) node, the S-CSCF node provides a policy indicator in a response message to a register request message. The policy indicator enables subsequent operation of the node to be controlled according to whether or not a registered UE has an associated policy. As such, delays (such as delays associated with retrieving an associated policy) are only experienced by UEs that have previously been determined as having such an associated policy, rather than all UEs being affected in the same way.