IP Multimedia Subsystem

About: IP Multimedia Subsystem is a research topic. Over the lifetime, 4398 publications have been published within this topic receiving 43698 citations.

Analysis of SIP in UMTS IP Multimedia Subsystem

Abstract: ZHU, BEI. Analysis of SIP in UMTS IP Multimedia Subsystem (Under the direction of Professor Arne A. Nilsson) As a key member of the 3G mobile technologies identified by the ITU (international Telecommunication Union), UMTS (Universal Mobile Telecommunications System) represents an evolution in terms of services and data speeds from today's 2G mobile networks. Third Generation Partnership Project (3GPP) was formed to work on the technical specification of UMTS. A UMTS network consists of three interacting domains: Core Network (CN), UMTS Terrestrial Radio Access Network (UTRAN) and User Equipment (UE). The IP multimedia subsystem comprises all CN elements for provision of multimedia services. The Session Initiation Protocol has been chosen by the 3GPP for establishing multimedia sessions in UMTS Release 5 networks. The purpose of the research has been to analyze the SIP operation in IP Multimedia Subsystem of UMTS network from two aspects: bottleneck and delay. The bottleneck analysis was based on the investigation of the detailed call set up and release procedures. The signaling flows hit each functional entities (CSCF or HSS) along the routing chains of signaling traffic several times. Once hit, the functional entity provides some service and then forwards the traffic on. We counted the hit times of each functional entity and identified the bottlenecks in different scenarios. We concluded that which one node would be the bottleneck depends on how the traffic is distributed in the networks. We did the delay analysis firstly by describing the SIP signaling traffic with M/M/1 notation. We calculated the delay in each node and gave the waiting time distribution. Then we assumed the traffic to be M/D/1 and gave the delay in each node. The total delay in a call set up/release procedure is the summation of the delay of the nodes along the signaling path. We got that the M/M/1 analysis provides us the upper bound of the average waiting time of each node, as well as the average delay in the call set up/release procedure. ANALYSIS OF SIP IN UMTS IP MULTIMEDIA SUBSYSTEM

Method and system for locating subscriber data in an IP multimedia subsystem

Abstract: A method for locating subscriber data in an IP multimedia subsystem is provided. The method includes receiving a subscriber location request for a user agent. The subscriber location request comprises a subscriber identifier that is operable to identify the user agent using one of at least two formats. One of a plurality of Home Subscriber Servers is identified as associated with the user agent based on the subscriber location request.

System and method for delivery of multimedia content into end-user devices

Abstract: An multimedia content interface system, computer program product, and method of operation provides multimedia content to a user without the user having to use a computer system, or other computation device. A multimedia content interface system for providing multimedia content stored on a data communications network to an end-user over another network, the multimedia content interface system communicatively connected to the data communications network and the other network, comprises a media delivery interface module operable to interface with the end-user over the other network, accept a request for multimedia content from the end-user, access multimedia content over the data communications network, and provide the multimedia content to the end-user over the other network and a content address translation module operable to provide an address mapping between an address of multimedia content stored on the data communications network and an address of the end-user on the other network.

Methods and apparatus to manage internet protocol (IP) multimedia subsystem (IMS) network capacity

Abstract: Methods and apparatus to manage Internet Protocol (IP) Multimedia Subsystem (IMS) network capacity are disclosed. An example method comprises identifying a terminating voice over Internet protocol (VoIP) call server associated with a called device, and returning a call rejection indicator when the terminating VoIP call server is in a first condition, the call rejection indicator returned without a call initiation request message sent to the terminating VoIP call server.