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Resource Management in Satellite Networks part 21. This book provides significant knowledge on innovative radio resource management schemes for satellite communication systems that exploit lower layer adaptivity and the knowledge of layer 3 IP QoS support and transport layer behavior. The book integrates competencies considering all the parts of system design: propagation aspects, radio resource management, access protocols, network protocols, transport layer protocols, and more, to cover both broadband and mobile satellite systems | Chapter 6 CALL ADMISSION CONTROL 183 accepted a handover reply message is sent to the mobile user. At this point buffering processes are needed to guarantee the minimum loss of cells. After the uplink downlink accesses are finished buffered cells will be transmitted through new links. As the Internet has become a ubiquitous communication infrastructure IP QoS provisioning is a strategic issue in any kind of network. A view that has been gaining considerable interest in the scientific community considers that the IP Integrated Services approach IntServ - service differentiation is focused on individual packet flows can be used in the wireless access networks in our case the satellite links in order to admit or to reject the requests of flows according to the availability of resources and the guarantees provided to other flows. On the other hand the IP Differentiated Services approach DiffServ - scalable service differentiation focused on the aggregate of flows can be employed to avoid complexity and maintenance of per-flow state information in the core network 14 15 . Both IntServ 15 16 and DiffServ 17 have been studied for satellite networks they are considered later in conjunction with CAC schemes. In general CAC schemes can be classified into those that offer Deterministic QoS Guarantees and those that provide Statistical QoS Guarantees 8 . Deterministic QoS guarantees a new connection is accepted provided that the worst-case scenario s requirements are met for instance the available capacity is greater than the peak rate of the connection . Although this approach represents the simplest solution for traffic management it tends to over-commit resources thus resulting in low link utilization. Statistical QoS guarantees in this case the NCC maintains a statistical allocation instead of guaranteeing a peak rate. Losses may occur but high channel utilization is accomplished. This approach is based on the assumption that having all the connections transmitting at .