Analysis to Prove Reservation-based Ad Hoc Wireless Systems is Better in Performance - Research Paper Example

Performance analysis to prove reservation based ad hoc wireless systems is better in performance when compared to non reservation based ad hoc systems. [26-08-2008] University STUDENT Contents Contents 2 Introduction 3 This paper outlines that how reservation based ad hoc wireless systems is better in performance when compared to non reservation based ad hoc systems. Below many points regarding reservation based ad hoc wireless systems and non reservation based ad hoc systems will be discussed. Most bandwidth reservation approaches for mobile ad hoc networks assume that all the nodes are cooperative and willing to transmit packets for other networks nodes or reserve resource for traffic that traverses neighboring nodes. 3 Analysis between reservation based and non reservation based approaches 3 Resource management support 3 QoS management support 4 Support for Real-time calls 5 Bandwidth allocation support 5 Real-time sessions Support 6 Network gaming 6 Maintaining and minimizing the routes interruptions 7 Packet delay/jitter and packet loss ratio 7 Conclusion 8 References 9 Introduction This paper outlines that how reservation based ad hoc wireless systems is better in performance when compared to non reservation based ad hoc systems. Below many points regarding reservation based ad hoc wireless systems and non reservation based ad hoc systems will be discussed. Most bandwidth reservation approaches for mobile ad hoc networks assume that all the nodes are cooperative and willing to transmit packets for other networks nodes or reserve resource for traffic that traverses neighboring nodes. Analysis between reservation based and non reservation based approaches Resource management support This section analyze how reservation based ad hoc wireless systems are better than non reservation based ad hoc wireless systems. Here general approach for resource management involves providing hard, soft and non real-time guarantees for local resources such as CPU and memory. In contrast, soft and non real-time guarantees are provided for communication resources. Notably, reservation based ad hoc wireless systems approach achieves a more efficient utilization of the resources whereby network bandwidth is reserved for hard real-time events whereas no resource reservation is made for soft and non real-time events. As there is a risk of soft real-time tasks to become overloaded, we additionally define reservations for soft real-time tasks obtained from two sources. Firstly, resources are obtained from those that were not reserved by hard real-time tasks. The second source is a bounded overlapping region with the resources assigned to hard real-time tasks. As a result, some soft real-time events will miss their deadlines when hard real-time events use this region but the probability of meeting their deadlines will increase. But as compared to non reservation based ad hoc wireless systems no such resource management at such level can be possible. Here in resources management it will be preferred to establish reservation based ad hoc wireless systems approach. QoS management support The highly dynamic nature of ad hoc networks makes the coordination of nodes competing for resources an essential issue. Therefore, task managers are introduced to control the allocation of resources according to both the QoS demands and the criticality of the tasks. There is a task manager per node. In reservation based ad hoc wireless systems, the resource management CF provides important support for the task managers in terms of resource awareness, resource reservation and resource reallocation. Resources for hard and soft real-time classes are statically reserved according to the defined tasks. For instance, when subscribing to a video on demand service supported by task y, resources are allocated if no other video sessions have been set up or enough resources are left for the new session. The resource requirements of announced and subscribed event types are obtained from a task information repository. As a result, resource allocation is granted for publishing and consuming events in the case of hard and soft real-time tasks. For that purpose, the task manager is in charge of requesting the appropriate resource managers to perform both the admission control tests and the reservation of resources when the test is successful. Where’s in non reservation based ad hoc wireless systems no such task manger is available that can mange, reserve and allocate resources. It is also important to mention that non reservation technique is not better for streaming data. For ad hoc network with streaming media the reservation based approach is best. Support for Real-time calls Since the nodes of an Ad hoc wireless network are free to move around, the protocol with which the network operates must be able to respond to a dynamically changing network topology. End-to-end reservation of bandwidth is the major approach for providing the necessary bandwidth for real-time calls. The major challenge in providing the end-to end reservation of bandwidth is the mobility of nodes, which causes frequent path breaks. The frequent path breaks demand reconfiguration of the path and associated resource reallocation. The examples of reservation based real-time traffic support are Multiple Access Collision Avoidance/Piggyback Reservation. But in non reservation based approaches due to no resource reservation there are many frequent path breaks in the real time call so this approach is not better for this type of serves. Bandwidth allocation support During a real time call you need a sufficient bandwidth, in reservation based approach bandwidth guarantee is demanded where reservation based schemes are preferred. The main issue associated with the scheduling schemes for providing bandwidth for real-time calls is the quality degradation due to contention when large number of node are present in the network (Al-kahtani, 2005). The scheduling based schemes are appropriate in a system where soft QoS (QoS provisioning mechanism where the failure to provide the performance level agreed upon, does not lead to disastrous effects) is sufficient whereas in tactical communications a more stringent bandwidth guarantee is demanded where reservation based schemes are preferred. While using non reservation approach you will get disastrous effects during a real time call due in sufficient bandwidth resources. Real-time sessions Support The issue of real-time communication and mobility, where the mobility awareness and prediction are proposed to perform proactive routing and resource reservation to allow meeting real-time constraints. Reservation based ad hoc wireless systems providing better quality for the real-time sessions in specific environments like the military where resources such as an additional interface and better power sources are available (Lee, 2000). This approach is especially suitable for Ad hoc wireless networks formed by a fleet of ships, a group of military tanks, or a set of military vehicles. While non reservation based ad hoc wireless systems in not suitable in such environment. Network gaming Now a days network gamming is more popular medium for ad hoc network. By using reservation based approach it possible to have sufficient bandwidth and data rate so that you can able to have such facility. But non reservation approach did not support such facility. Maintaining and minimizing the routes interruptions Maintaining and minimizing the routes interruptions are two ways of keeping the stability of the network (Al-kahtani, 2005). It is analyzed that the lifetime of a particular route is dependent on the entire cluster heads involved in this route. By maintaining the route lifetime, it can keep the network in stable condition as long as possible. Therefore, resource reservation (LC3R) approach is the only solution for such type of problem. But in non resources reservation approach you can not avoid route interruption. So the communication over ad hoc wireless network systems is not better supported by non resources reservation approach, because Packets may be dropped in the middle, if the lifetime of a route between nodes is shorter than the time required in transmitting them, so if route or its resources are not reserved than handling such situation is not possible and this thing is results of failure of this technique. Packet delay/jitter and packet loss ratio With reservation based approach packets delay/jitter and packet loss ratio will be improved (Al-kahtani, 2005). Therefore, the protocol increases the level of reliability of packet transmissions as requested by the connection. But in non reservation based approach no sufficient bandwidth and other resources are available so it is not better to incorporate non reservation approach in ad hoc wireless network, because there is more he packet loss rates in it. Conclusion This paper has considered the QoS issues in ad hoc networks using reservation based or non reservation based approach for ad hoc wireless systems. Here after analyzing so many points related to ad hoc wireless network it is concluded that reservation based approach is more efficient and better for wireless ad hoc network. There are lot more other points that also belong to this comparison but her I have tried to analyze more popular and impotent points. References 1. M. S. Al-kahtani, H. T. Mouftah 2005 ‘A Stable Clustering Formation Infrastructure Protocol in Mobile Ad Hoc Networks,’; accepted at IEEE Int. Conf. on Wireless and Mobile Computing, Networking and Communications (WiMob2005), Montreal, Canada. 2. S. J. Lee and M. Gerla 2000 ‘AODV-BR: Backup Routing in Ad hoc Networks’; In Proceedings of the IEEE Wireless Communications and Networking Conference( WCNC), pp. 1311-1316. Read More