Topic
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.
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03 Jul 2001
TL;DR: A comparison of the methods to implement services in SIP and H.323 focusing on the service architectures and their capabilities regarding the implementation of new features is provided.
Abstract: Among the different solutions providing multimedia teleconferencing services over IP networks, two approaches are of major importance: H.323 standardized by the ITU-T and SIP standardized by the IETF. Some comparisons on a system level have been published, but the service architectures have rarely been addressed in the literature. In the near future an important driver for multimedia business will be the services and the mechanisms for their fast and efficient service development and deployment. We provide a comparison of the methods to implement services in SIP and H.323 focusing on the service architectures and their capabilities regarding the implementation of new features. While H.323 is still the more mature standard-albeit SIP tends to keep up-the two protocols have basic differences in the supplementary services architectures. H.323/H.450 has been defined as a sophisticated enterprise solution and is well suited to support complex multimedia calls involving widely interoperable supplementary services. SIP on the other side represents a more universal approach. SIP uses more generic syntax and semantics regarding feature definition and session description, which carries the danger to cause interworking problems. The advantage of SIP is its general applicability for signaling non-VoIP sessions for example the establishment of a PSTN session as standardized in the PINT approach.
22 citations
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18 Mar 2008
TL;DR: In this article, the authors present systems and methods for presenting a multimedia object to a handset in conjunction with voice call from a circuit switched (CS) network and the multimedia object is delivered over a packet-switched (PS) network.
Abstract: The present invention provides systems and methods for presenting a multimedia object to a handset in conjunction with voice call from a circuit switched (CS) network. The voice call is delivered over the CS network and the multimedia object is delivered over a packet-switched (PS) network. The multimedia object can be rendered as a voice call alert, during the voice call, or after the voice call. The multimedia object can be an advertisement object and can be provided by a third party. The systems and methods described are applicable to IMS and non-IMS networks.
22 citations
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08 Apr 2015
TL;DR: In this paper, the authors proposed a determination method for a voice service scheme of a VoLTE (Voice over Long Term Evolution) terminal and the VOLTE terminal by reselecting from a 2G/3G (Two-Generation/Three-generation) cell to an LTE cell according to cell signal intensity measured in a preset range.
Abstract: The invention provides a determination method for a voice service scheme of a VoLTE (Voice over Long Term Evolution) terminal and the VoLTE terminal. The method comprises the following steps: reselecting from a 2G/3G (Two-Generation/Three-Generation) cell to an LTE cell by the VoLTE terminal according to cell signal intensity measured in a preset range; if a reselected LTE cell identity is stored at the VoLTE terminal, transmitting a first position updating request to a mobile management entity MME by the VoLTE terminal, wherein a VoLTE voice service scheme restriction identity is carried in the first position updating request, so an IMS (IP Multimedia Subsystem) unregistration request message of the VoLTE terminal is transmitted to an IMS by a home subscriber server HSS according to the VoLTE voice service scheme restriction identity carried in a first position updating message; receiving, by the VoLTE terminal, an IMS unregistration success response message transmitted by the IMS; determining circuit switched fallback CSFB according to the IMS unregistration success response message to serve as the voice service scheme of the VoLTE terminal to perform the voice service.
22 citations
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30 Mar 2007TL;DR: In IP Multimedia Subsystem (IMS) IMS Control Channel Protocol (ICCP) is used between a user equipment (UE) and ICCF and Session Initiated Protocol (SIP) interface (between to ICCF, Call Session Control Function and Application Server) to support the indication of circuit switched (CS) access utilizing P-Access-Network-lnformation header as discussed by the authors.
Abstract: In IP Multimedia Subsystem (IMS) IMS Control Channel Protocol (ICCP) is used between a user equipment (UE) and IMS Control Channel Function (ICCF) and Session Initiated Protocol (SIP) interface (between to ICCF, Call Session Control Function and Application Server) to support the indication of Circuit Switched (CS) access utilizing P-Access-Network-lnformation header. The indication can be used by an S-CSCF or AS for different purposes such as routing decision, charging, and presence info.
22 citations
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13 Nov 2007TL;DR: In this article, a method for triggering an IMS (IP Multimedia Subsystem) registration in the IMS, includes sending, by network side or a user who initiates the triggering, a IMS registration triggering indication message to the user who needs the registration to initiate the registration.
Abstract: A method for triggering an IMS (IP Multimedia Subsystem) registration in the IMS, includes sending, by network side or a user who initiates the triggering, an IMS registration triggering indication message to a user who needs the IMS registration, to prompt the user who needs the IMS registration to initiate the IMS registration to the IMS; according to the IMS registration triggering indication message, trigging the user who needs the IMS registration to initiate the IMS registration to the IMS. Since the network side or the user who initiates the triggering triggers the IMS registration for the user who needs the IMS registration, the problem that the SIP messages may not be issued to the user who needs the IMS registration and the IMS session may not be performed because the user who needs the IMS registration does not register in the IMS during the IMS session, can be avoided.
22 citations