QoS Guarantee Mechanisms In All-IP Wireless Mobile Networks

Internet Protocol (IP) has been the focus in recent years, which is considered as the key technology of the next generation network. Guaranteeing the quality-of-service (QoS) is the essential problem in the research of Internet. IETF presents two models, i.e. Intserv and Diffserv, so as to solve the problem of QoS in IP network.RSVP (ReSource Reservation Protocol) is the most popular signaling protocol in Intserv model, which is receiver-initiated and makes flow-based end-to-end resource reservation. Because of the presence of mobile hosts, however, RSVP could not be directly used, such that it should be changed. Thanks to the user's mobility, it is more difficult to guarantee QoS in mobile network than in wired network. The mobility of the host has great importance on the QoS parameters of real-time application. The QoS parameters of real-time application include packet delay, packet loss rate and delay jitter. When mobile host changes its position, the route of the flow changes, which may causes the change of packet delay as routers on the new route may gain different path length and queuing delay. In wireless networks, small cells are used to get more system capacity such that handoff is more frequent and it is more difficult to guarantee QoS.With all-IP mobile networks, it is necessary to make advanced resource reservation to provide QoS during handoff. Otherwise, it is hard to get the desired resource in time, e.g. bandwidth. Therefore, a model that combines micro-mobility protocol and RSVP is presented. A RSVP path re-routing mechanism is discussed, which could mimimize the delay of resource reservation and overload of signaling during handoff, therefore minimizing the degradation of service. Moreover, a scheme of dynamic RSVP resource allocation on wireless links is presented. However, it is impossible to make resource reservation to make full use of resource when several mobile hosts begin to handoff. Then, it is important to make order of them to effectively make resource reservation. As we know now, there is little knowledge about this. There may be some methods for it, such as making random selection of the mobile hosts to handoff. Some provide signal prediction priority queuing (SPPQ) to queue the mobile hosts to handoff. This paper makes some improvement on SPPQ to make priority ordering for mobile hosts. Then, it could not only predict which mobile hosts to handoff, but also effectively reserves...