• IEMEK Journal of Embedded Systems and Applications
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• v.15 no.5
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• pp.251-259
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• 2020

Ad hoc On-demand Distance Vector (AODV) protocol and its variants employ two important timers, hello and hold timer to keep track of topology changes. Moreover, hold timer is computed by multiplying constant value to hello timer. But, this configuration leads to inaccurate settings of hold timer. To solve this problem, in this paper, we propose a new dynamic adjustment of hello and hold timer scheme by removing dependency between them. A new metric to measure mobility is applied into hello timer, while expected link lifetime does holder timer. Simulation results show a significant reduction in the number of messages, a fact suggesting that it is possible to maintain and in some cases improve the performance of AODV with a minimum amount of messages released into the network.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.596-598
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• 2003

다중홉 (multi-hop) 이동 애드혹 앙 (ad-hoc network)에서 무결정성 (seamless) 통신이 이루어지기 위해 효율적인 라우팅 프로토콜을 필요로 한다. AODV (Ad-hoc On-demand Distance Vector) 라우팅 프로토콜은 단지 먼저 수신된 경로 요구 (route request) 메시지가 전달되어 온 경로만을 고려 할 뿐, 경로 탐색 과정에 있어 각 노드에서의 에너지 사용량을 반영하지 못하고 있다. 이 논문에서는 AODV 라우팅 프로토콜에 기존에 제안된 MTPR (Minimum Total Transmission Power Routing) 방법을 효율적으로 적용할 수 있는 경로 탐색 방법을 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.11B
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• pp.981-988
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• 2008

In this paper, the efficient AODV routing algorithm in MANET is proposed. Because transmission channel has a high error rate and loss in MANET, the number of hops can't be regarded as an absolute network metric. After measuring FER periodically at the data link layer using cross-layer design, the scheme that every node forwards the weight of link status in the reserved field of AODV protocol is used. In order to find the efficient route, we design AODV to be able to select an optimal route that has a good channel status by evaluating the sum of weight. The proposed AODV improves throughput, routing overhead and average end-to-end delay in comparison with the generic AODV.

• Journal of the Korea Society of Computer and Information
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• v.14 no.1
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• pp.117-125
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• 2009

In hybrid wireless networks, a mobile node in MANET can communicate with other mobile nodes as well as nodes in the Internet. Hybrid mobile networks help to expand the application domains of MANET from limited areas, such as military applications to more diverse and general application areas. Previous routing protocols in hybrid wireless networks have not taken advantage of location information of nodes in a network. By using location information of nodes, a routing protocol can reduce the overhead of control messages for efficient network operations. This paper proposes a routing protocol for hybrid mobile networks, called Location-aided AODV+ (LAp) that is based on ADOV+ and takes advantage of node's location information. Performance evaluation shows that LAp performs better than ADOV+ when there are a sufficient number of nodes in a network for route establishments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.5
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• pp.1354-1372
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• 2012

Route establishment in Mobile Ad Hoc Network (MANET) is the key mechanism to a successful connection between a pair of source and destination nodes. An efficient routing protocol constructs routing path with minimal time, less routing overhead and capable of utilizing all possible link connectivity. In general, most on-demand MANET routing protocols operates over symmetrical and bidirectional routing path, which is infeasible due to the inherent heterogeneous properties of wireless devices. Simulation results show that the presence of unidirectional links on a network severely affect the performance of a routing protocol. In this paper, a robust protocol independent scheme is proposed, which enable immediate rediscovery of alternative route for a path blocked by a unidirectional link. The proposed scheme is efficient; route rediscovery is locally computed, which results in significant minimization of multiple route packets flooding. Nodes may exploit route information of immediate neighbors using the local reply broadcast technique, which then redirect the control packets around the unidirectional links, therefore maintaining the end-to-end bidirectional connection. The proposed scheme along with Ad Hoc On-demand Distance Vector (AODV) and AODV-Blacklist routing protocol is investigated over three types of mobility models. Simulation results show that the proposed scheme is extremely reliable under poor network conditions and the route connectivity can be improved by as much as 75%.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.3
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• pp.469-477
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• 2008

The standard routing protocol of MANET(Mobile Ad-hoc NETwork), AODV(Ad-hoc On-demand Distance Vector), only considers the shortest path for routing, which may cause traffic concentration to a node at the critical path. Hence, the battery of the node will be dissipated rapidly to reduce the lifetime of the whole network. In this paper, power dissipation considered AODV is proposed for fair energy distribution in MANET, and verified using the computer simulation.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.55-65
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• 2010

We present a method for increasing network lifetime without link failure due to lack of battery capacity of nodes in wireless ad-hoc networks with low mobility. In general, a node with larger remaining battery capacity represents the one with lesser traffic load. Thus, a modified AODV routing protocol is proposed to determine a possible route by considering a remaining battery capacity of a node. Besides, the total energy consumption of all nodes increase rapidly due to the huge amount of control packets which should be flooded into the network. To reduce such control packets efficiently, a source node can store information about alternative routes to the destination node into its routing table. When a link failure happens, the source node should retrieve the route first with the largest amount of the total remaining battery capacity from its table entries before initiating the route rediscovery process. To do so, the possibility of generating unnecessary AODV control packets should be reduced. The method proposed in this paper increases the network lifetime by 40% at most compared with the legacy AODV and MMBCR.

• The KIPS Transactions:PartC
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• v.13C no.4 s.107
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• pp.447-454
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• 2006

An ad-hoc network routing protocol, AODV(Ad-hoc On-demand Distance Vector) initially uses ERS(Expanding Ring Search) algorithm to control the RREQ(Route Request) retransmission in the route discovery process. Because ERS uses the fixed NTT(Node Travesal Time), it does not reflect accurately ad-hoc network environment. In this paper, we propose an improved ERS algorithm which lowers the retransmission rate. It uses RREP(Route Reply) and gives different weights in NTT of each node in accordance with the adjacency to an originating node. To show the effectiveness of the proposed algorithm, we perform a simulation using ns2. The simulation results showed that the proposed algorithm has better performance than existing algorithms.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.1-8
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• 2021

In Mobile Ad-Hoc Network (MANET) Application, routing protocol is essential to ensure successful data transmission to all nodes. Ad-hoc On-demand Distance Vector (AODV) Protocol is a reactive routing protocol that is mostly used in MANET applications. However, the protocol causes Route Request (RREQ) message flooding issue due to the broadcasting method at the route request stage to find a path to a particular destination, where the RREQ will be rebroadcast if no Request Response (RREP) message is received. A scalable neighbor-based routing (SNBR) protocol was then proposed to overcome the issue. In the SNBR protocol, the RREQ message is only rebroadcast if the number of neighbor nodes less than a certain fix number, known as drop factor. However, since a network always have a dynamic characteristic with a dynamic number of neighbor nodes, the fix drop factor in SNBR protocol could not provide an optimal flooding problem solution in a low dense network environment, where the RREQ message is continuously rebroadcast RREQ message until reach the fix drop factor. To overcome this problem, a new broadcasting method as Dynamic SNBR (DSNBR) is proposed, where the drop factor is determined based on current number of neighbor nodes. This method rebroadcast the extra RREQ messages based on the determined dynamic drop factor. The performance of the proposed DSNBR is evaluated using NS2 and compared with the performance of the existing protocol; AODV and SNBR. Simulation results show that the new routing protocol reduces the routing request overhead, energy consumption, MAC Collision and enhances end-to-end delay, network coverage ratio as a result of reducing the extra route request messages.

• Journal of KIISE:Information Networking
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• v.30 no.2
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• pp.252-259
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• 2003

In the case of link congestion, most of the existing ad-hoc routing protocols like AODV and DSR do not try to discover a new route if there is no change in the network topology. Hence, with low mobility, traffic may get concentrated on some specific nodes. Since mobile devices have low battery power and low computing capability, traffic concentration on a specific node is not a desirable phenomenon. Therefore, in this paper, we propose a new protocol called SLAP (Simple Load-balancing Ad-hoc routing Protocol) which resolves the traffic concentration problem by letting each node check its own load situation and give up its role as a packet forwarder gracefully in the case of high traffic load. We compare the performance of SLAP with that of AODV and DSR in terms of the forwarding traffic distribution.