Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper w...Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper we present Maximally Spatial Disjoint Multipath routing protocol (MSDM) which is a modification of AOMDV protocol. MSDM finds paths which are spatially separated and maximally disjointed. We think that sending various packets over spatially disjointed paths reduces the probability of collision occurrence and allows concurrent transmission over the set of different selected paths. Performance comparison of MSDM and AOMDV using GloMoSim simulator shows that MSDM is able to achieve a considerable improvement regarding some performance metrics such as delay, routing packets overhead, and network throughput.展开更多
In mobile ad hoc networks （MANETs）, if a mnltihop route breaks, route maintenance is typically performed to establish a new route which causes high control overhead and long packet delay. To decrease the time of rec...In mobile ad hoc networks （MANETs）, if a mnltihop route breaks, route maintenance is typically performed to establish a new route which causes high control overhead and long packet delay. To decrease the time of recovery and the overhead of maintenance, a new route maintenance mechanism in which the maintenance is confined to the vicinity of the broken link is proposed. This mechanism patches broken route through some other nodes in which only nodes near the broken link（s） may need to be substituted and the rest of nodes can be retained on the route. The broken link can be repaired without considering its relative position in the whole path, so the abihty of dealing with hnk failure is improved obviously. Simulation results show that the proposed strategy improves network performance significantly, such as in merits of control overhead and packet delay.展开更多
Routing on ad-hoc network has become a major research issue among the networking communities due to its increasing complexity and the surge of challenging problems. One major factor contributing to this tendency is th...Routing on ad-hoc network has become a major research issue among the networking communities due to its increasing complexity and the surge of challenging problems. One major factor contributing to this tendency is that every terminal of an ad-hoc network is also functioning as a network router. In this paper we provide a comprehensive review about the principles and mechanisms of routing protocols used in ad-hoc networks. For comparison purposes, we discuss some relevant technical issues of two well-known routing strategies, namely On-Demand (Proactive routing) and Table-Driven (Reactive routing). In particular, focus our attention on two major and well-known routing protocols: AODV (Ad-hoc On-Demand Distance Vector Protocol) and OLSR (Optimized Link State Routing Protocol). Our study has no intention to suggest any definite solution for any ad-hoc network, because it is the case depending on dictated by the nature and varying factors of networks. Instead, we demonstrate our major perception and describe general models that may assist us while modeling a given network.展开更多
To cope with the problem of low protocol efficiency of the standard ad hoc on-demand distance vector （AODV） routing protocol with the periodic Hello message broadcast mechanism, a new link availability prediction ba...To cope with the problem of low protocol efficiency of the standard ad hoc on-demand distance vector （AODV） routing protocol with the periodic Hello message broadcast mechanism, a new link availability prediction based strategy is introduced to reduce the amount of Hello messages. In this strategy, a novel wireless link availability prediction model under line-of-sight （LOS） propagation environments is proposed based on which the parameter of Hello Interval in AODV can be dynamically adjusted to achieve the goal of changing the frequency of Hello message broadcasts under different link stability degrees. Simulation results demonstrate that, compared with the standard AODV with the periodic Hello message broadcast mechanism, the proposed protocol effectively reduces unnecessary control message overhead and greatly improves the performance in terms of end-to-end delay and efficiency.展开更多
Due to highly dynamic topology caused by fast moving nodes the Vehicular ad-hoc network (VANET) results in the existence of transient communication links, which degrade the performance of developed protocols. Establis...Due to highly dynamic topology caused by fast moving nodes the Vehicular ad-hoc network (VANET) results in the existence of transient communication links, which degrade the performance of developed protocols. Established routes frequently become stale, and existing communication flows are interrupted, incurring delay and additional overhead. In this paper we propose a novel hybrid routing protocol, which is the combined between of the table-driven routing and on-demand routing in VANET. It makes fast convergence in routing process, minimal drop links, making more reliable links, and adaptive with changing of VANET topology. With neighbor table is updated instantaneously, and using strong neighbor for routing process makes route discovery process start whenever it received requirement, and through using route mechanism appropriately it reduces significantly route overhead at each node. The simulation results illustrate the outstanding properties of our proposed routing protocol.展开更多
Subarea Tree Routing (STR), a new routing protocol for multi-hop wireless ad hoc networks, is proposed. The novelty of the STR protocol is to divide the whole network into many subareas constructed as a result of esta...Subarea Tree Routing (STR), a new routing protocol for multi-hop wireless ad hoc networks, is proposed. The novelty of the STR protocol is to divide the whole network into many subareas constructed as a result of establishing subarea trees. Its main idea is to identify root nodes by manual configuration or auto-discovery process firstly, then the root nodes originate the process of establishing subarea trees, and finally each node either joins in a subarea tree or become an interconnect node. STR belongs to hierarchical routing protocol and does not attempt to consistently maintain routing information in every node. Furthermore, through the use of tree’s intrinsic routing function, the STR protocol exhibits hybrid behavior of proactive and on-demand routing protocols. We prove the correctness of STR, and our simulation results show that the pro-posed scheme achieves lower route discovery delays, lower route discovery load and better performance of normalized routing load in large, mobile, ad hoc networks as compared with AODV.展开更多
In MANETs, traffic may follow certain pattern that is not necessarily spatial or temporal but rather to follow special needs as a part of group for collaboration purposes. The source node tends to communicate with a c...In MANETs, traffic may follow certain pattern that is not necessarily spatial or temporal but rather to follow special needs as a part of group for collaboration purposes. The source node tends to communicate with a certain set of nodes more than others regardless of their location exhibiting traffic locality where this set changes over time. We introduce a traffic locality oriented route discovery algorithm with delay, TLRDA-D. It utilises traffic locality by establishing a neighbourhood that includes the most likely destinations for a particular source node. The source node broadcasts the route request according to the original routing used. However, each intermediate node broadcasts the route request with a delay beyond this boundary to give priority for route requests that are travelling within their own source node’s neighbourhood region. This ap-proach improves the end-to-end delay and packet loss, as it generates less contention throughout the network. TLRDA-D is analysed using simulation to study the effect of adding a delay to route request propagation and to decide on the amount of the added delay.展开更多
Internet of Things(IoT)networks are characterized by a multitude of wireless,interconnected devices that can dynamically join or exit the network without centralized administration or fixed infrastructure for routing....Internet of Things(IoT)networks are characterized by a multitude of wireless,interconnected devices that can dynamically join or exit the network without centralized administration or fixed infrastructure for routing.While multipath routing in IoT networks can improve data transmission reliability and load balancing by establishing multiple paths between source and destination nodes,these networks are susceptible to security threats due to their wireless nature.Traditional security solutions developed for conventional networks are often ill-suited to the unique challenges posed by IoT environments.In response to these challenges,this paper proposes the integration of the Ad hoc On-demand Multipath Distance Vector(AOMDV)routing protocol with a trust model to enhance network performance.Key findings from this research demonstrate the successful fusion of AOMDV with a trust model,resulting in tangible improvements in network performance.The assessment of trustworthiness bolsters both security and routing capabilities in IoT networks.The trust model plays a crucial role in mitigating black hole attacks in IoT networks by evaluating the trustworthiness of nodes and helping in the identification and avoidance of malicious nodes that may act as black holes.Simulation results validate the efficacy of the proposed trust-based routing mechanism in achieving its objectives.Trust plays a pivotal role in decision-making and in the creation of secure distribution systems.By assessing the trustworthiness of nodes,both network security and routing efficiency can be enhanced.The effectiveness of the proposed trust-based routing mechanism is scrutinized through simulations,offering insights into its potential advantages in terms of improved network security and routing performance in the context of the IoT.展开更多
文摘Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper we present Maximally Spatial Disjoint Multipath routing protocol (MSDM) which is a modification of AOMDV protocol. MSDM finds paths which are spatially separated and maximally disjointed. We think that sending various packets over spatially disjointed paths reduces the probability of collision occurrence and allows concurrent transmission over the set of different selected paths. Performance comparison of MSDM and AOMDV using GloMoSim simulator shows that MSDM is able to achieve a considerable improvement regarding some performance metrics such as delay, routing packets overhead, and network throughput.
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 mnltihop route breaks, route maintenance is typically performed to establish a new route which causes high control overhead and long packet delay. To decrease the time of recovery and the overhead of maintenance, a new route maintenance mechanism in which the maintenance is confined to the vicinity of the broken link is proposed. This mechanism patches broken route through some other nodes in which only nodes near the broken link（s） may need to be substituted and the rest of nodes can be retained on the route. The broken link can be repaired without considering its relative position in the whole path, so the abihty of dealing with hnk failure is improved obviously. Simulation results show that the proposed strategy improves network performance significantly, such as in merits of control overhead and packet delay.
文摘Routing on ad-hoc network has become a major research issue among the networking communities due to its increasing complexity and the surge of challenging problems. One major factor contributing to this tendency is that every terminal of an ad-hoc network is also functioning as a network router. In this paper we provide a comprehensive review about the principles and mechanisms of routing protocols used in ad-hoc networks. For comparison purposes, we discuss some relevant technical issues of two well-known routing strategies, namely On-Demand (Proactive routing) and Table-Driven (Reactive routing). In particular, focus our attention on two major and well-known routing protocols: AODV (Ad-hoc On-Demand Distance Vector Protocol) and OLSR (Optimized Link State Routing Protocol). Our study has no intention to suggest any definite solution for any ad-hoc network, because it is the case depending on dictated by the nature and varying factors of networks. Instead, we demonstrate our major perception and describe general models that may assist us while modeling a given network.
基金The National High Technology Research and Development Program of China (863Program)(No2006AA01Z268)
文摘To cope with the problem of low protocol efficiency of the standard ad hoc on-demand distance vector （AODV） routing protocol with the periodic Hello message broadcast mechanism, a new link availability prediction based strategy is introduced to reduce the amount of Hello messages. In this strategy, a novel wireless link availability prediction model under line-of-sight （LOS） propagation environments is proposed based on which the parameter of Hello Interval in AODV can be dynamically adjusted to achieve the goal of changing the frequency of Hello message broadcasts under different link stability degrees. Simulation results demonstrate that, compared with the standard AODV with the periodic Hello message broadcast mechanism, the proposed protocol effectively reduces unnecessary control message overhead and greatly improves the performance in terms of end-to-end delay and efficiency.
基金Sponsored by the National Science and Technology Major Project(Grant No. 2010ZX03005-003)
文摘Due to highly dynamic topology caused by fast moving nodes the Vehicular ad-hoc network (VANET) results in the existence of transient communication links, which degrade the performance of developed protocols. Established routes frequently become stale, and existing communication flows are interrupted, incurring delay and additional overhead. In this paper we propose a novel hybrid routing protocol, which is the combined between of the table-driven routing and on-demand routing in VANET. It makes fast convergence in routing process, minimal drop links, making more reliable links, and adaptive with changing of VANET topology. With neighbor table is updated instantaneously, and using strong neighbor for routing process makes route discovery process start whenever it received requirement, and through using route mechanism appropriately it reduces significantly route overhead at each node. The simulation results illustrate the outstanding properties of our proposed routing protocol.
文摘Subarea Tree Routing (STR), a new routing protocol for multi-hop wireless ad hoc networks, is proposed. The novelty of the STR protocol is to divide the whole network into many subareas constructed as a result of establishing subarea trees. Its main idea is to identify root nodes by manual configuration or auto-discovery process firstly, then the root nodes originate the process of establishing subarea trees, and finally each node either joins in a subarea tree or become an interconnect node. STR belongs to hierarchical routing protocol and does not attempt to consistently maintain routing information in every node. Furthermore, through the use of tree’s intrinsic routing function, the STR protocol exhibits hybrid behavior of proactive and on-demand routing protocols. We prove the correctness of STR, and our simulation results show that the pro-posed scheme achieves lower route discovery delays, lower route discovery load and better performance of normalized routing load in large, mobile, ad hoc networks as compared with AODV.
文摘In MANETs, traffic may follow certain pattern that is not necessarily spatial or temporal but rather to follow special needs as a part of group for collaboration purposes. The source node tends to communicate with a certain set of nodes more than others regardless of their location exhibiting traffic locality where this set changes over time. We introduce a traffic locality oriented route discovery algorithm with delay, TLRDA-D. It utilises traffic locality by establishing a neighbourhood that includes the most likely destinations for a particular source node. The source node broadcasts the route request according to the original routing used. However, each intermediate node broadcasts the route request with a delay beyond this boundary to give priority for route requests that are travelling within their own source node’s neighbourhood region. This ap-proach improves the end-to-end delay and packet loss, as it generates less contention throughout the network. TLRDA-D is analysed using simulation to study the effect of adding a delay to route request propagation and to decide on the amount of the added delay.
文摘Internet of Things(IoT)networks are characterized by a multitude of wireless,interconnected devices that can dynamically join or exit the network without centralized administration or fixed infrastructure for routing.While multipath routing in IoT networks can improve data transmission reliability and load balancing by establishing multiple paths between source and destination nodes,these networks are susceptible to security threats due to their wireless nature.Traditional security solutions developed for conventional networks are often ill-suited to the unique challenges posed by IoT environments.In response to these challenges,this paper proposes the integration of the Ad hoc On-demand Multipath Distance Vector(AOMDV)routing protocol with a trust model to enhance network performance.Key findings from this research demonstrate the successful fusion of AOMDV with a trust model,resulting in tangible improvements in network performance.The assessment of trustworthiness bolsters both security and routing capabilities in IoT networks.The trust model plays a crucial role in mitigating black hole attacks in IoT networks by evaluating the trustworthiness of nodes and helping in the identification and avoidance of malicious nodes that may act as black holes.Simulation results validate the efficacy of the proposed trust-based routing mechanism in achieving its objectives.Trust plays a pivotal role in decision-making and in the creation of secure distribution systems.By assessing the trustworthiness of nodes,both network security and routing efficiency can be enhanced.The effectiveness of the proposed trust-based routing mechanism is scrutinized through simulations,offering insights into its potential advantages in terms of improved network security and routing performance in the context of the IoT.
