| 摘要 |
<p>The invention relates to a method of establishing a session between client user terminals accessing IP Multimedia Subsystem, IMS, networks. At least one of the IMS networks implements the use of Quality of Service, QoS, preconditions, and at least one of the client user terminals does not use QoS preconditions. The method includes receiving, at an inter-working function, IWF located in one of the IMS networks, an IMS session initiation request originated by an originating client, the request indicating a terminating client for the session. A decision is made, based on the session initiation request, that one of the originating client and the terminating client is not using QoS preconditions. A set of QoS preconditions is inserted into a procedure for establishing the IMS session on behalf of the client that is not using QoS preconditions. Session establishment is completed only after QoS resources complying with the set of QoS preconditions have been established.</p> |
