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Most important frameworks supporting mobile communications are not capable of meeting real-time application requirements because of the service degradation appearing during the handover process. Such degradation is mainly noticed as an excessive blocking time and a non-negligible packet loss rate. This is due to slow procedures for address allocati...
Contexts in source publication
Context 1
... layer information corresponds to MGLT, SHP and POC procedures. A special procedure recovers this information and generates at least three data packets, which are sent to the corresponding network entities (see Figure 5 and Figure 6). As far as correspondent node and location directory are concerned, their protocol stack is not modified. ...
Citations
Service continuity is an important component in mobile communications. With the coexistence of different access network technologies and the emergence of multi-interface mobile devices, service providers should maintain the ongoing communication when the mobile travels among heterogeneous networks. Services like IPTV, video on demand or voice over IP are widely proposed by operators for which service continuity should be guaranteed. This thesis is devoted to service continuity of real-time applications in heterogeneous networks. We tackle this problem from two perspectives: session mobility and terminal mobility. Although these two mechanisms have the same purpose which is ensuring service continuity when changing the terminal or the access network, each technique has its own challenges and constraints. As far as session mobility is concerned, a new signaling protocol has been proposed to transfer the session between different terminals. This protocol has been implemented in video streaming scenarios and evaluated in a testbed. Moreover, we address the problem of media adaptation, especially renegotiation of QoS parameters since session might be transferred to a new terminal with different capabilities than the original one. QoS renegotiation can be extended to cover the case where some internal parameters are degraded during the session in the same terminal. For terminal mobility, we propose a new handover mechanism using IEEE802.21 with Fast handover for Mobile IPv6. The purpose of this proposal is to reduce the handover delay and the dedicated buffer in access routers. In addition, an optimization is proposed for Fast handovers for Mobile IPv6 in order to maximize the probability of its predictive mode. In the same context, mobility in IMS is considered and an appropriate solution is proposed to answer IMS requirements. Finally, we conduct a comparison study between different mobile IP variants in the case of vertical handover. Based on this comparison, we give some guidelines that should help in choosing the most efficient protocol following specific parameters. The proposed solutions and studies have been evaluated analytically or/and using a simulation tool.
IMS is the new approach adopted by 3GPP towards networks convergence. It was designed to be access independent and ubiquitous. IMS already provides personal mobility for nomadic users, but still needs to deal with service continuity within non 3GPP networks. In this paper we propose a novel hybrid mobility management scheme, based on tight cooperation between fast handovers for mobile IPv6 (FMIPv6) and session initiation protocol (SIP) to ensure an uninterrupted real-time service. Moreover, the new Media Independent Handover (MIH) service is integrated into the IMS architecture in order to perform intelligent and accurate horizontal and vertical handovers. The handover is managed in two phases. The first one or the fast phase is handled by FMIPv6 protocol to preserve as soon as possible packets of the ongoing communication. The second one or the slow phase is handled by the SIP protocol to optimize packet delivery route. By doing so, we exploit the benefits of both layer 3 and application mobility protocols to ensure a continuous session over the two networks without imposing new elements to the network. Through a comparison with other mobility mechanisms, we show in the analytic analysis that our hybrid scheme presents better results in terms of handover latency and packet loss.
