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In multi-hop networks, Adaptive Quality of Service routing (AQoS or AQR) protocols have become increasingly popular and have numerous applications. One application in which it may be useful is in Mobile ad hoc networking (MANET). Adaptive QoS routing is a cross-layer optimization adaptive routing mechanism. The cross-layer mechanism provides up-to-date local QoS information for the adaptive routing algorithm, by considering the impacts of node mobility and lower-layer link performance. The multiple QoS requirements are satisfied by adaptively using forward error correction and multipath routing mechanisms, based on the current network status. The complete routing mechanism includes three parts: (1) a modified dynamic source routing algorithm that handles route discovery and the collection of QoS related parameters; (2) a local statistical computation and link monitoring function located in each node; and (3) an integrated decision-making system to calculate the number of routing paths, coding parity length, and traffic distribution rates. The adaptive cooperation concept has future promises to overcome infrastructure loaded approaches and to get rid of central facilities with autonomous networks in industrial and home applications. The United States Air Force is determining the best way to employ QoS protocols into Airborne Networking. Research composed shows that Adaptive QoS that uses cross-layer cooperation has provided the best results for military applications. == Introduction == A wireless ad hoc network consists of a collection of mobile nodes interconnected by multihop wireless paths with wireless transmitters and receivers. Such networks can be spontaneously created and operated in a self-organized manner, because they do not rely upon any preexisting network infrastructure. The emergence of multimedia applications in communications has generated the need to provide mobile quality-of-service (QoS) support in ad hoc networks, and such applications require a stable path to guarantee QoS requirements. However, the topology of ad hoc networks is highly dynamic due to the unpredictable node mobility. In addition, wireless channel bandwidth is limited. So, QoS provisioning in such networks is complex and challenging. QoS routing usually involves two tasks: collecting and maintaining up-to-date state information about the network and finding feasible paths for a connection based on its QoS requirements. Many approaches currently exist to perform QoS routing, most of which consist of routing across the Network layer of the OSI model only. Some approaches utilize both the Network and Data link layer but do not consider the cross layer behaviors. This makes quantifying the QoS parameters difficult and leads to considerations of QoS but does not guarantee QoS. To address this problem, appropriate cross-layer cooperation is required. Adaptive QoS schemes provide QoS information by factoring the impacts of node mobility and lower-layer link parameters into QoS performance. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Adaptive quality of service multi-hop routing」の詳細全文を読む スポンサード リンク
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