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Resource Management in Satellite Networks part 28

Resource Management in Satellite Networks part 28. 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 | 256 Ulla Birnbacher Wei Koong Chai Fig. 8.9 Short time scale behavior of SWTP showing its predictability property. See reference 10 . Copyright @2005 IEEE. 8.4 QoS mapping over satellite-independent service access point In what follows we are specifically concerned with the cross-layer interaction between the network and the MAC layer in order to preserve QoS requirements or in more precise terms to operate a mapping between the QoS mechanisms operating at the two layers. Within a more general view with reference to the ETSI Broadband Satellite Multimedia BSM protocol architecture 15 16 we might refer to the inter-working between the Satellite-Independent SI and the Satellite-Dependent SD architectural components at the SI-SAP Satellite-Independent - Service Access Point by taking into account both the change in encapsulation format and the traffic aggregation in the passage from SI to SD queues. Note that the ETSI BSM architecture has been described in Chapter 1 Section 1.5. Cross-layer RRM problems involving network and MAC layers have been extensively considered in 17 - 19 . Reference 20 also provides guidelines and architectural details. In particular in 17 - 19 Dynamic Bandwidth Allocation DBA is applied by computing bandwidth requests for each Earth station s DiffServ queue which are passed to a centralized scheduler typically residing in a Master Control Station MCS . The latter assigns the bandwidth proportionally to the requests received the remaining capacity is assigned on a free basis. Such scheme has been called Combined Free Demand Assignment Multiple Access CF DAMA . In a similar context the problem of QoS mapping between adjacent layers has been recently treated in 21 - 23 . Rather than considering specifically the Chapter 8 RESOURCE MANAGEMENT AND NETWORK LAYER 257 network and the MAC layers the problem is posed in the more general ETSI BSM scenario mentioned above. In the presence of IP DiffServ queues at the higher layer the problem consists in .