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An Advanced Approach for Distance Vector Routing Protocol Babel

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An Advanced Approach for Distance Vector Routing Protocol Babel Volume 1, Issue 4, December 2013 ISSN: 2320-9984 (Online) International Journal of Modern Engineering & Management Research Website: www.ijmemr.org An Advanced Approach for Distance Vector Routing Protocol Babel Deshraj Ahirwar Mukesh Kumar Dhariwal Assistant Professor Assistant Professor Department of Computer Science & Engineering Department of Computer Science & Engineering University Institute of Technology, RGPV, University Institute of Technology, RGPV, Bhopal (M.P.) [INDIA] Bhopal (M.P.) [INDIA] Email :[email protected] Email : [email protected] Sanjay Kumar Tehariya Abhishek Kesharwani Assistant Professor Assistant Professor Department of Computer Science & Engineering Department of Computer Science & Engineering University Institute of Technology, RGPV, University Institute of Technology, RGPV Bhopal (M.P.) [INDIA] Bhopal (M.P.) [INDIA] Email : [email protected] Email : [email protected] Abstract—This type of protocols maintains the absence of routing pathologies, such as fresh lists of destinations and their routes by routing loops. periodically distributing routing tables throughout the network. The main disadvantages of such algorithms are: Respective amount of data for maintenance. And Slow reaction on restructuring and failures. It is loop-avoidance vector routing protocol. The Babel routing protocol is a distance-vector routing protocol for Internet Protocol packet-switched network that is designed to be robust and efficient on both wireless mesh networks and wired networks. Keywords:— MANET, IPv4, TTL, distance Figure 1: Node configuration in babel network vector routing, routing table, etc. Babel operates on IPv and IPv networks. It has been reported to be a robust protocol and 1. INTRODUCTION to have fast convergence properties.[1][2] Babel is based on the ideas Two implementations of Babel are freely in Destination-Sequenced Distance Vector available: the standalone sample routing (DSDV), Ad hoc On-Demand Distance implementation, and a version that is integrated Vector Routing (AODV), and Cisco's into the Quagga routing suite.[3][4] The Enhanced Interior Gateway Routing Protocol version integrated into Quagga allows for (EIGRP), but it uses a variant of Expected authentication.[5] a table-driven routing Transmission Count (ETX) link cost scheme for ad hoc mobile network based on estimation rather than a simple hop-count the Bellman–Ford algorithm. It was developed metric. It employs several techniques to ensure by C. Perkins and P. Bhagwat in 1994. The main contribution of the algorithm was to International Journal of Modern Engineering & Management Research | Vol 1 | Issue 4 | Dec. 2013 23 An Advanced Approach for Distance Vector Routing Protocol Babel Author (s) : Deshraj Ahirwar, Mukesh Kumar Dhariwal, Sanjay Kumar Tehariya, Abhishek Kesharwani | UIT, Bhopal solve the routing loop problem. Each entry in Whenever the topology of the network the routing table contains a sequence number, changes, a new sequence number is necessary the sequence numbers are generally even if a before the network re-converges; thus, DSDV link is present; else, an odd number is used. is not suitable for highly dynamic networks. The number is generated by the destination, (As in all distance-vector protocols, this does and the emitter needs to send out the next not perturb traffic in regions of the network update with this number. Routing information that are not concerned by the topology is distributed between nodes by sending full change.) itself does not appear to be much used dumps infrequently and smaller incremental today[citation needed], other protocols have updates more frequently. used similar techniques. Figure 2: Node combination in adhoc network Destina- Next Number Se- Install Figure 3: Combination of networking devices and node tion Hop of Hops quence Time in adhoc network Number The best-known sequenced distance A A 0 A 46 001000 vector protocol is AOD, which, by virtue of being a reactive protocol, can use simpler sequencing heuristics. Babe is an attempt at B B 1 B 36 001200 making DSDV more robust, more efficient and more widely applicable while staying within C B 2 C 28 001500 the framework of proactive protocols. Table 1: Routing table in adhoc network A RouteRequest carries the source identifier (SrcID), the destination 2. RELATED WORK identifier (DestID), the source sequence If a router receives new information, number (SrcSeqNum), the destination then it uses the latest sequence number. If the sequence number (DestSeqNum), the sequence number is the same as the one broadcast identifier (BcastID), and the time to already in the table, the route with the better live (TTL) field. DestSeqNum indicates the metric is used. Stale entries are those entries freshness of the route that is accepted by the that have not been updated for a while. Such source. When an intermediate node receives a entries as well as the routes using those nodes RouteRequest, it either forwards it or prepares as next hops are deleted. a RouteReply if it has a valid route to the destination. The validity of a route at the DSDV requires a regular update of its intermediate node is determined by comparing routing tables, which uses up battery power the sequence number at the intermediate node and a small amount of bandwidth even when with the destination sequence number in the the network is idle. RouteRequest packet. If a RouteRequest is International Journal of Modern Engineering & Management Research | Vol 1 | Issue 4 | Dec. 2013 24 An Advanced Approach for Distance Vector Routing Protocol Babel Author (s) : Deshraj Ahirwar, Mukesh Kumar Dhariwal, Sanjay Kumar Tehariya, Abhishek Kesharwani | UIT, Bhopal received multiple times, which is indicated by The needy node then begins using the the BcastID-SrcID pair, the duplicate copies route that has the least number of hops through are discarded. All intermediate nodes having other nodes. Unused entries in the routing valid routes to the destination, or the table are recycled after a time. destination node itself, are allowed to send RouteReply packets to the source. Every When a link fails, a routing error is intermediate node, while forwarding a passed back to a transmitting node, and the RouteRequest, enters the previous node process repeats. address and its BcastID. A timer is used to Much of the complexity of delete this entry in case a RouteReply is not the protocol is to lower the number of received before the timer expires. This helps in messages to conserve the capacity of the storing an active path at the intermediate node network. For example, each request for a route as AODV does not employ source routing of has a sequence number. Nodes use this data packets. When a node receives a sequence number so that they do not repeat RouteReply packet, information about the route requests that they have already passed previous node from which the packet was on. Another such feature is that the route received is also stored in order to forward the requests have a "time to live" number that data packet to this next node as the next hop limits how many times they can be toward the destination. retransmitted. Another such feature is that if a route request fails, another route request may 3. WORKING not be sent until twice as much time has passed The network is silent until a connection as the timeout of the previous route request. is needed. At that point the network node that needs a connection broadcast a request for connection. Other AODV nodes forward this message, and record the node that they heard it from, creating an explosion of temporary routes back to the needy node. When a node receives such a message and already has a route to the desired node, it sends a message backwards through a temporary route to the requesting node. Layer Attacks Application layer Repudiation, data corruption Figure 4: Babel architecture Transport layer Session hijacking, SYN The advantage of AODV is that it creates flooding no extra traffic for communication along Network layer Wormhole, blackhole, flooding, existing links. Also, distance vector routing is location discloser attacks simple, and doesn't require much memory or calculation. However AODV requires more Data link layer Traffic analysis, monitoring, time to establish a connection, and the initial disruption, MAC(802.11), communication to establish a route is heavier WEP, weakness than some other approaches. Physical layer Jamming interceptions Routing Protocol uses an on-demand approach for finding routes, that is, a route is established only when it is required by a source Table 2: Various attacks in layered architecture node for transmitting data packets. It employs destination sequence numbers to identify the International Journal of Modern Engineering & Management Research | Vol 1 | Issue 4 | Dec. 2013 25 An Advanced Approach for Distance Vector Routing Protocol Babel Author (s) : Deshraj Ahirwar, Mukesh Kumar Dhariwal, Sanjay Kumar Tehariya, Abhishek Kesharwani | UIT, Bhopal most recent path. The major difference In addition to the routing table, EIGRP between AODV and Dynamic Source also uses the following tables to store Routing (DSR) stems out from the fact that information:- DSR uses source routing in which a data packet carries the complete path to be Neighbor Table: The neighbor table traversed. keeps a record of the IP address of router that have a direct However, in AODV, the source node physical connection with this router. and the intermediate nodes store the next-hop Routers that are connected to this information corresponding to each flow for router indirectly, through another data packet transmission. In an on-demand router are not recorded in this table routing protocol, the source node floods as they are not considered the RouteRequest packet in the network when a neighbours. route is not available for the desired destination. It may obtain multiple routes to Topology Table: The topology table different destinations from a stores routes that it has learned from single RouteRequest. The major difference neighbour routing tables.
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