Tham khảo tài liệu 'mobile ad hoc networks protocol design part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 32 Mobile Ad-Hoc Networks Protocol Design Based on the interaction between the routing protocol and the QoS provisioning mechanism QoS approaches can be divided into Coupled and Decoupled Shah Nahrstedt 2002 . 1. In Coupled QoS the routing protocol and the QoS provisioning mechanism directly interact with each other for delivering the required QoS. 2. In Decoupled QoS the QoS provisioning mechanism does not depend on any specific routing protocol with the intention of having required QoS. In addition QoS approaches can be categorized as independent and dependent based on the interaction between the routing protocol and the MAC protocol Murthy Manoj 2004 . In independent QoS the network layer is not dependent on the MAC layer QoS provisioning. While for dependent QoS it requires the MAC layer to support the routing protocol for QoS provisioning. Figure 8 illustrates some ad-hoc network routing protocols each one established for a particular purpose http secan-lab . Fig. 8. Some ad-hoc routing protocols algorithms Quality of Service QoS Provisioning in Mobile Ad-Hoc Networks MANETs 33 As can be seen routing strategies can be also categorized as adaptive routing and not-Adaptive routing. For Ad-Hoc-Networks only adaptive strategies are useful http . Accordingly the route selection strategies are characterized as follows power-aware routing signal strength link stability shortest path link-state routing and distance-vector routing. Furthermore QoS approaches based on the routing information update mechanism can be classified as table-driven on-demand and hybrid Mbarushimana Shahrabi 2007 . 1. Table-driven Pro-Active each node in the network holds a routing table which can support the forwarding packets. The routing tables are called periodically or event-driven and it will be only updated if any change happens in the network. The main disadvantages of table-driven QoS are bandwidth consumption in transmitting routing tables and also saving .
