SNGF Selected Node Geographic Forwarding Routing Protocol for VANETs

VANET;Routing;Protocol;Traffic Profiling;Electrical and Computer Engineering

Vaqar, Sayyid

University of Waterloo

关键词: VANET;    Routing;    Protocol;    Traffic Profiling;    Electrical and Computer Engineering;   

Others  :  https://uwspace.uwaterloo.ca/bitstream/10012/5782/1/VAQAR_SAYYID.pdf

瑞士|英语

来源: UWSPACE Waterloo Institutional Repository

【 摘 要 】

This thesis presents a protocol for intervehicle communication for use in VehicularAd Hoc Networks (VANET). VANET is a natural extension of mobile adhoc networks (MANET) in which the restrictions related to power and mobilityare relaxed. The routing protocols used for MANETs are generally dependent onthe state of the network. With changes in the network topology, routing messagesare generated so that the states of the routers in the network are updated. Inthe case of VANETs, in which the level of node mobility is high, message-routingoverhead has serious implications for the scalability and throughput of the routingprotocol.This thesis introduces criteria that are recommended for use when protocolsare designed for VANET applications and presents the Selected Node GeographicForwarding (SNGF) protocol. The SNGF protocol implements controlled floodingin an efficient manner in order to reduce unnecessary communication overhead.The protocol has a destination discovery mechanism that allows it to initiatecorrespondence between nodes without reliance on static location services. Theprotocol avoids formation of clusters by using the concept of selective forwarding,thus providing the advantages of cluster based approaches without actuallyforming one itself. It effectively deals with blind flooding by introducing a comprehensiveretransmission time delay in the nodes. This retransmission delayfavors the nodes in the direction of the destination and prevents other nodesfrom retransmitting the same message. The SNGF protocol does not use routingtables, which require frequent updates in mobile networks, instead it relies on directing the messages to geographic locations which are forwarded by anyavailable intermediary nodes. The protocol also provides techniques for handlingnetwork fragmentation which can be a frequent problem in vehicular networks.It is capable of delayed message transmission and multiple route discovery in thecase of the non-availability of the shortest path to the destination.To evaluate the performance of the SNGF protocol, an extensive study ofmobile networks was conducted using the NS2 simulator. The simulation resultsdemonstrate the reachability of the protocol, its scalability advantages and itstotal independence from location services.The SNGF protocol allows each participating node to operate independentlyof other nodes in the network. Nodes in the network are able to communicatewith other nodes without ever becoming dependent on intermediary nodes. Thisfeature opens new possibility for individual node based application developmentin ad hoc networks. The traffic profiling is described as it would be observed by anindependent node participating in VANET using the SNGF protocol. The nodecommunicates with other nodes and collects relevant data through the discoursecapability of SNGF. The data collected by the node is viewed as a snapshot intime of the traffic conditions down the road based upon which future traffic conditionis predicted. Traffic profiling is investigated for different levels of VANETdeployment. The simulation results show that the proposed method of trafficprofiling in a VANET environment using the SNGF protocol is viable for evenlower levels of deployment.