will further specify the detailed traffic parameters and QoS parameters. For QoS-guaranteed service provisioning, the network operator must configure DiffServ-over-MPLS virtual overlay networks for differentiated services. The scalability can be achieved by using a virtual overlay network to configure the predefined paths for different traffic classes. If a specific application service is agreed via SLA, a session setup and a con- nection establishment for the media application should be initiated using QoS- extended SIP (Q-SIP)/SDP and RSVP-TE signaling. Q-SIP/SDP will be used to find the current location of the destination, and to determine the availabil- ity and capability of the RoS-aware station (RSTA) terminal for the requested multimedia application. The Q-SIP proxy server may utilize a location server to provide some value-added service based on presence and availability man- agement functions. The sending Q-SIP/SDP user agent will offer the list of possible media types and encoding standards, and the receiving Q-SIP/SDP user agent, considering its processing capacity, will select some acceptable media type and its encoding format, and reply with the acceptable list to the sender. Finally, the sending Q-SIP/SDP user agent will determine the selected media type and the encoding format to be used in the multimedia session. Once a multimedia session description is agreed upon by the participants, a QoS-guaranteed per-class-type end-to-end connection establishment will be requested through UNI signaling. If the multimedia communication service is using a separated connection for each media type, multiple connections should be established for each media-type packet flow. As an end-to-end connec- tion establishment signaling, RSVP-TE can be used in the backbone transit IP/MPLS network. The edge node (router) of the ingress provider network should take the role of connection control and management functions for on- demand connection establishments [10]. When the user's terminal is attached to a contention-based 