Resource Management in Satellite Networks part 7. 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 1 INTRODUCTION TO SATELLITE COMMUNICATIONS 37 An example of the first method is when cross-layer signaling is provided through the SI-SAP to connect the management of the layer 3 queues with that of layer 2 ones . information regarding the length of the layer 2 queue used by layer 3 . This mechanism is important to support QoS. In particular the SI layer requests layer 2 queue status information through a C-plane primitive namely a REQUEST primitive and the SD layer answers by means of another C-plane primitive namely a CONFIRM primitive . As already stated it is possible that BPM manages this information exchange. Finally an example of cross-layer information exchange not involving the use of SI-SAP is that between layer 1 and layer 2. Such signalling can be used for the MODCOD switching of DVB-S2. In such case a C-plane primitive is used to request to notify or to update information respectively REQUEST INDICATION and RESPONSE primitives . Conclusions Satellite systems are an attractive solution to provide multimedia communication services in wide areas of the Earth also reaching those regions that lack of terrestrial telecommunication infrastructures. In this framework this Chapter has provided an introduction to the features of satellites for communications including orbit types GEO MEO LEO atmospheric attenuation phenomena and related packet losses multiple access schemes and the air interfaces of main interest for this book . S-UMTS and DVB-S -S2 -RCS . In this Chapter a special attention has been also given to the basic aspects characteristics constraints etc. related to the management of satellite resources in S-UMTS and DVB-S -S2 -RCS systems. Such information will be essential in the study of the resource management schemes that will be carried out in the next Chapters each addressing these techniques from a different prospective. This Chapter has also provided three main scenarios with numerical details that will be adopted for .
