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232
Mitigating routing misbehavior in mobile ad hoc networks
- Proc. ACM/IEEE MOBICOM
, 2000
"... This paper describes two techniques that improve through-put in an ad hoc network in the presence of nodes that agree to forward packets but fail to do so. To mitigate this prob-lem, we propose categorizing nodes based upon their dynam-ically measured behavior. We use a watchdog that identifies misb ..."
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Cited by 1065 (4 self)
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This paper describes two techniques that improve through-put in an ad hoc network in the presence of nodes that agree to forward packets but fail to do so. To mitigate this prob-lem, we propose categorizing nodes based upon their dynam-ically measured behavior. We use a watchdog that identifies misbehaving nodes and a patl~rater that helps routing pro-tocols avoid these nodes. Through simulation we evaluate watchdog and pathrater using packet throughput, percent-age of overhead (routing) transmissions, and the accuracy of misbehaving node detection. When used together in a net-work with moderate mobility, the two techniques increase throughput by 17 % in the presence of 40 % misbehaving nodes, while increasing the percentage ofoverhead transmis-sions from the standard routing protocol's 9 % to 17%. Dur-ing extreme mobility, watchdog and pathrater can increase network throughput by 27%, while increasing the overhead transmissions from the standard routing protocol's 12 % to 24%. 1.
A Scalable Location Service for Geographic Ad Hoc Routing
"... GLS is a new distributed location service which tracks mobile node locations. GLS combined with geographic forwarding allows the construction of ad hoc mobile networks that scale to a larger number of nodes than possible with previous work. GLS is decentralized and runs on the mobile nodes themselve ..."
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Cited by 774 (18 self)
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GLS is a new distributed location service which tracks mobile node locations. GLS combined with geographic forwarding allows the construction of ad hoc mobile networks that scale to a larger number of nodes than possible with previous work. GLS is decentralized and runs on the mobile nodes themselves, requiring no fixed infrastructure. Each mobile node periodically updates a small set of other nodes (its location servers) with its current location. A node sends its position updates to its location servers without knowing their actual identities, assisted by a predefined ordering of node identifiers and a predefined geographic hierarchy. Queries for a mobile node’s location also use the predefined identifier ordering and spatial hierarchy to find a location server for that node. Experiments using the ns simulator for up to 600 mobile nodes show that the storage and bandwidth requirements of GLS grow slowly with the size of the network. Furthermore, GLS tolerates node failures well: each failure has only a limited effect and query performance degrades gracefully as nodes fail and restart. The query performance of GLS is also relatively insensitive to node speeds. Simple geographic forwarding combined with GLS compares favorably with Dynamic Source Routing (DSR): in larger networks (over 200 nodes) our approach delivers more packets, but consumes fewer network resources.
Capacity of Ad Hoc Wireless Networks
"... Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns, and detailed local radio interactions. This paper examine ..."
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Cited by 626 (14 self)
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Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns, and detailed local radio interactions. This paper examines these factors alone and in combination, using simulation and analysis from first principles. Our results include both specific constants and general scaling relationships helpful in understanding the limitations of wireless ad hoc networks. We examine interactions of the 802.11 MAC and ad hoc forwarding and the effect on capacity for several simple configurations and traffic patterns. While 802.11 discovers reasonably good schedules, we nonetheless observe capacities markedly less than optimal for very simple chain and lattice networks with very regular traffic patterns. We validate some simulation results with experiments. We also show that the traffic pattern determines whether an ad hoc network’s per node capacity will scale to large networks. In particular, we show that for total capacity to scale up with network size the average distance between source and destination nodes must remain small as the network grows. Non-local traffic patterns in which this average distance grows with the network size result in a rapid decrease of per node capacity. Thus the question “Are large ad hoc networks feasible?” reduces to a question about the likely locality of communication in such networks.
On-demand Multipath Distance Vector Routing in Ad Hoc Networks
- in Proceedings of IEEE International Conference on Network Protocols (ICNP
, 2001
"... We develop an on-demand, multipath distance vector protocol for mobile ad hoc networks. Specifically, we propose multipath extensions to a well-studied single path routing protocol known as Ad hoc On-demand Distance Vector (AODV). The resulting protocol is referred to as Ad hoc Ondemand Multipath Di ..."
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Cited by 342 (3 self)
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We develop an on-demand, multipath distance vector protocol for mobile ad hoc networks. Specifically, we propose multipath extensions to a well-studied single path routing protocol known as Ad hoc On-demand Distance Vector (AODV). The resulting protocol is referred to as Ad hoc Ondemand Multipath Distance Vector (AOMDV). The protocol computes multiple loop-free and link-disjoint paths. Loopfreedom is guaranteed by using a notion of "advertised hopcount." Link-disjointness of multiple paths is achieved by using a particular property of flooding. Performance comparison of AOMDV with AODV using ns-2 simulations shows that AOMDV is able to achieve a remarkable improvement in the end-to-end delay --- often more than a factor of two, and is also able to reduce routing overheads by about 20%. 1
Performance Comparison of Two On-demand Routing protocols for Ad Hoc Networks
, 2001
"... Ad hoc networks are characterized by multihop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols. We compare the performance of two prominent on-demand routing protocols for mobile ad hoc networks: Dynamic Source Routing (DSR) and Ad Hoc ..."
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Cited by 247 (1 self)
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Ad hoc networks are characterized by multihop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols. We compare the performance of two prominent on-demand routing protocols for mobile ad hoc networks: Dynamic Source Routing (DSR) and Ad Hoc On-Demand Distance Vector Routing (AODV). A detailed simulation model with MAC and physical layer models is used to study interlayer interactions and their performance implications. We demonstrate that even though DSR and AODV share similar ondemand behavior, the differences in the protocol mechanics can lead to significant performance differentials. The performance differentials are analyzed using varying network load, mobility, and network size. Based on the observations, we make recommendations about how the performance of either protocol can be improved.
An evaluation of inter-vehicle ad hoc networks based on realistic vehicular traces
- In MobiHoc ’06: Proceedings of the seventh ACM international symposium on Mobile ad hoc networking and computing
, 2006
"... Vehicular ad hoc networks (VANETs) using WLAN technology have recently received considerable attention. The evaluation of VANET routing protocols often involves simulators since management and operation of a large number of real vehicular nodes is expensive. We study the behavior of routing protocol ..."
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Cited by 144 (3 self)
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Vehicular ad hoc networks (VANETs) using WLAN technology have recently received considerable attention. The evaluation of VANET routing protocols often involves simulators since management and operation of a large number of real vehicular nodes is expensive. We study the behavior of routing protocols in VANETs by using mobility information obtained from a microscopic vehicular traffic simulator that is based on the on the real road maps of Switzerland. The performance of AODV and GPSR is significantly influenced by the choice of mobility model, and we observe a significantly reduced packet delivery ratio when employing the realistic traffic simulator to control mobility of nodes. To address the performance limitations of communication protocols in VANETs, we investigate two improvements that increase the packet delivery ratio and reduce the delay until the first packet arrives. The traces used in this study are available for public download. Categories and Subject Descriptors:
Detection and Handling of MAC Layer Misbehavior in Wireless Networks
, 2002
"... Selfish hosts in wireless networks that fail to adhere to the MAC protocol may obtain an unfair share of the channel bandwidth. We present modifications to the IEEE 802.11 backoff mechanism to simplify detection of such selfish hosts. We also present a correction scheme for penalizing greedy misbeha ..."
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Cited by 142 (2 self)
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Selfish hosts in wireless networks that fail to adhere to the MAC protocol may obtain an unfair share of the channel bandwidth. We present modifications to the IEEE 802.11 backoff mechanism to simplify detection of such selfish hosts. We also present a correction scheme for penalizing greedy misbehavior which attempts to restrict the misbehaving nodes to a fair share of the channel bandwidth. Simulation results indicate that our detection and correction schemes are fairly successful in handling MAC layer misbehavior.
The Effects of On-Demand Behavior in Routing Protocols for Multi-Hop Wireless Ad Hoc Networks
- IEEE Journal on Selected Areas in Communications
, 1999
"... Abstract—A number of different routing protocols proposed for use in multi-hop wireless ad hoc networks are based in whole or in part on what can be described as on-demand behavior. By ondemand behavior, we mean approaches based only on reaction to the offered traffic being handled by the routing pr ..."
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Cited by 137 (10 self)
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Abstract—A number of different routing protocols proposed for use in multi-hop wireless ad hoc networks are based in whole or in part on what can be described as on-demand behavior. By ondemand behavior, we mean approaches based only on reaction to the offered traffic being handled by the routing protocol. In this paper, we analyze the use of on-demand behavior in such protocols, focusing on its effect on the routing protocol’s forwarding latency, overhead cost, and route caching correctness, drawing examples from detailed simulation of the dynamic source routing (DSR) protocol. We study the protocol’s behavior and the changes introduced by variations on some of the mechanisms that make up the protocol, examining which mechanisms have the greatest impact and exploring the tradeoffs that exist between them. Index Terms—Communication system routing, computer network performance, dynamic source routing (DSR) protocol, wireless ad hoc networks. I.
Effects of power conservation, wireless coverage and cooperation on data dissemination among mobile devices
- PROCEEDINGS OF ACM MOBIHOC
, 2001
"... This paper presents 7DS, a novel peer-to-peer data sharing system. 7DS is an architecture, a set of protocols and an implementation enabling the exchange of data among peers that are not necessarily connected to the Internet. Peers can be either mobile or stationary. It anticipates the information n ..."
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Cited by 136 (10 self)
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This paper presents 7DS, a novel peer-to-peer data sharing system. 7DS is an architecture, a set of protocols and an implementation enabling the exchange of data among peers that are not necessarily connected to the Internet. Peers can be either mobile or stationary. It anticipates the information needs of users and fulfills them by searching for information among peers. We evaluate via extensive simulations the effectiveness of our system for data dissemination among mobile devices with a large number of user mobility scenarios. We model several general data dissemination approaches and investigate the effect of the wireless coverage range, 7DS host density, query interval and cooperation strategy among the mobile hosts. Using theory from random walks, random environments and diffusion of controlled processes, we model one of these data dissemination schemes and show that the analysis confirms the simulation results for this scheme.
