In mobile ad hoc networks(MANETs),if a muhihop route breaks,route maintenance is typicallyperformed to establish a new route which causes high control overhead and long packet delay.To decreasethe time of recovery and...In mobile ad hoc networks(MANETs),if a muhihop route breaks,route maintenance is typicallyperformed to establish a new route which causes high control overhead and long packet delay.To decreasethe time of recovery and the overhead of maintenance,a new route maintenance mechanism in which themaintenance is confined to the vicinity of the broken link is proposed.This mechanism patches brokenroute through some other nodes in which only nodes near the broken link(s)may need to be substitutedand the rest of nodes can be retained on the route.The broken link can be repaired without consideringits relative position in the whole path,so the ability of dealing with link failure is improved obviously.Simulation results show that the proposed strategy improves network performance significantly,such as inmerits of control overhead and packet delay.展开更多
A novel reliable routing algorithm in mobile ad hoc networks using fuzzy Petri net with its reasoning mechanism was proposed to increase the reliability during the routing selection. The algorithm allows the structure...A novel reliable routing algorithm in mobile ad hoc networks using fuzzy Petri net with its reasoning mechanism was proposed to increase the reliability during the routing selection. The algorithm allows the structured representation of network topology, which has a fuzzy reasoning mechanism for finding the routing sprouting tree from the source node to the destination node in the mobile ad hoc environment. Finally, by comparing the degree of reliability in the routing sprouting tree, the most reliable route can be computed. The algorithm not only offers the local reliability between each neighboring node, but also provides global reliability for the whole selected route. The algorithm can be applied to most existing on-demand routing protocols, and the simulation results show that the routingreliability is increased by more than 80% when applying the proposed algorithm to the ad hoc on demand distancevector routing protocol.展开更多
In Shadow-Fading model, it is difficult to achieve higher Packet Delivery Ratio (PDR) due to the effects of large scale fading. The main goal of this paper is to improve the PDR in Shadow-Fading environment. To achiev...In Shadow-Fading model, it is difficult to achieve higher Packet Delivery Ratio (PDR) due to the effects of large scale fading. The main goal of this paper is to improve the PDR in Shadow-Fading environment. To achieve this objective a protocol has been proposed that discovers backup routes for active sessions. These backup routes salvage the packets of active session in case of active route failure. It is found by research that proactively maintaining backup routes for ac-tive sessions can noticeably improve the PDR in Shadow-Fading environment. This protocol has been implemented with a mechanism of having backup routes and simulations have been conducted by using both node disjoint paths and link disjoint paths. Comparisons have been made between new protocol as well as AODV protocol. Simulation has been carried out using Network Simulator 2 (NS2) and the results show that the proposed QoSAR protocol exhibits higher PDR than AODV protocol in Shadow-fading environment.展开更多
In location-aided routing of Mobile Ad hoc NETworks(MANET),nodes mobility and the inaccuracy of location information may result in constant flooding,which will reduce the network performance.In this paper,a Distance-B...In location-aided routing of Mobile Ad hoc NETworks(MANET),nodes mobility and the inaccuracy of location information may result in constant flooding,which will reduce the network performance.In this paper,a Distance-Based Location-Aided Routing(DBLAR) for MANET has been proposed.By tracing the location information of destination nodes and referring to distance change between nodes to adjust route discovery dynamically,the proposed routing algorithm can avoid flooding in the whole networks.Besides,Distance Update Threshold(DUT) is set up to reach the balance between real-time ability and update overhead of location information of nodes,meanwhile,the detection of relative distance vector can achieve the goal of adjusting forwarding condition.Simulation results reveal that DBLAR performs better than LAR1 in terms of packet successful delivery ratio,average end-to-end delay and routing-load,and the set of DUT and relative distance vector has a significant impact on this algorithm.展开更多
基金the National High Technology Research and Development Progamme of China(No2005AA123820)the National Natural Science Foundation of China(No60472052 and No10577007)
文摘In mobile ad hoc networks(MANETs),if a muhihop route breaks,route maintenance is typicallyperformed to establish a new route which causes high control overhead and long packet delay.To decreasethe time of recovery and the overhead of maintenance,a new route maintenance mechanism in which themaintenance is confined to the vicinity of the broken link is proposed.This mechanism patches brokenroute through some other nodes in which only nodes near the broken link(s)may need to be substitutedand the rest of nodes can be retained on the route.The broken link can be repaired without consideringits relative position in the whole path,so the ability of dealing with link failure is improved obviously.Simulation results show that the proposed strategy improves network performance significantly,such as inmerits of control overhead and packet delay.
文摘A novel reliable routing algorithm in mobile ad hoc networks using fuzzy Petri net with its reasoning mechanism was proposed to increase the reliability during the routing selection. The algorithm allows the structured representation of network topology, which has a fuzzy reasoning mechanism for finding the routing sprouting tree from the source node to the destination node in the mobile ad hoc environment. Finally, by comparing the degree of reliability in the routing sprouting tree, the most reliable route can be computed. The algorithm not only offers the local reliability between each neighboring node, but also provides global reliability for the whole selected route. The algorithm can be applied to most existing on-demand routing protocols, and the simulation results show that the routingreliability is increased by more than 80% when applying the proposed algorithm to the ad hoc on demand distancevector routing protocol.
文摘In Shadow-Fading model, it is difficult to achieve higher Packet Delivery Ratio (PDR) due to the effects of large scale fading. The main goal of this paper is to improve the PDR in Shadow-Fading environment. To achieve this objective a protocol has been proposed that discovers backup routes for active sessions. These backup routes salvage the packets of active session in case of active route failure. It is found by research that proactively maintaining backup routes for ac-tive sessions can noticeably improve the PDR in Shadow-Fading environment. This protocol has been implemented with a mechanism of having backup routes and simulations have been conducted by using both node disjoint paths and link disjoint paths. Comparisons have been made between new protocol as well as AODV protocol. Simulation has been carried out using Network Simulator 2 (NS2) and the results show that the proposed QoSAR protocol exhibits higher PDR than AODV protocol in Shadow-fading environment.
基金Supported by National 863 High Technology Research and Development Program Foundation of China (No.2006AA-01Z208)Six Talented Eminence Foundation of Jiangsu Province (06-E-043), China+1 种基金Natural Science Foundation of Jiangsu Province, China (No.BK2007236)Scientific Innovation Project for Postgraduates of Universities in Jiangsu Province (CX08B-082Z)
文摘In location-aided routing of Mobile Ad hoc NETworks(MANET),nodes mobility and the inaccuracy of location information may result in constant flooding,which will reduce the network performance.In this paper,a Distance-Based Location-Aided Routing(DBLAR) for MANET has been proposed.By tracing the location information of destination nodes and referring to distance change between nodes to adjust route discovery dynamically,the proposed routing algorithm can avoid flooding in the whole networks.Besides,Distance Update Threshold(DUT) is set up to reach the balance between real-time ability and update overhead of location information of nodes,meanwhile,the detection of relative distance vector can achieve the goal of adjusting forwarding condition.Simulation results reveal that DBLAR performs better than LAR1 in terms of packet successful delivery ratio,average end-to-end delay and routing-load,and the set of DUT and relative distance vector has a significant impact on this algorithm.
