Routing Protocols in Mobile Ad-Hoc Networks

Mobile ad hoc NetworksAn hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any infrastructure or centralized stand-alone ad hoc networks are administration.Mobile self-organization and self-configuring networks where wireless multihop , the structure of the network changes dynamically. This is mainly due to the mobility of the nodes [8]. The nodes of these networks use the same random access channel wireless, working in a friendly manner to themselves engaged in multi-hop forwarding. The nodes of the network not only acts as a host, but also as routers that route data to / from other nodes of the network. In mobile ad hoc networks where no infrastructure support as is the case with wireless networks, and as a destination may not be out of the reach of a source node to transmit packets, a routing procedure is always need to find a way for Sun to transmit packets as appropriate between the source and destination. Within a cell, a base station can reach all the mobile nodes, without routing via broadcast common in wireless networks. In the case of ad hoc networks, each node must be able to transmit data to other nodes. . This creates additional problems along with problems of dynamic changes in topology • What is unpredictable connectivity problem with routing in mobile ad hoc net-works-asymmetric links: Most cable networks are based on symmetric and left are always fixed. But this is not a case with ad-hoc networks, as nodes are mobile and constantly changing their position within the network. For example, consider a MANET (Mobile Ad hoc Network), where the node B sends a signal to node A, but this says nothing about the quality of the connection in the opposite direction -. Head of routing in wireless ad hoc networks, none of often change their position within the network. Well, some sections are not updated in the routing table generated which leads to unnecessary overhead routing -. This interference is the main problem with mobile ad hoc networks as connections come and go depending on the characteristics of transmission, a transmission may interfere with another de and can not hear the transmissions of other nodes and can totally corrupt the transmission -. dynamic topology This is also the main problem with routing ad hoc since the topology is not constant. The mobile node may move or may change the average characteristics. In ad hoc networks, routing tables must somehow reject these changes in the topology and routing algorithms must be adapted. For example in a fixed network routing table update occurs for every 30 sec. This refresh rate may be very low for ad hoc networks. • Classification of routing protocols in MANET'sClassification of routing protocols in MANET can be done in many ways, but most of these are made according to the routing strategy and network structure. According to the strategy of routing protocols can be classified as table-driven routing and source initiated, depending on the structure of the network while they are classified as routing, hierarchical routing and location-assisted routing. Both protocols initiated on the table-driven and the source covered by the flat routing.Table-driven routing protocols (Proactive) These protocols are also called as proactive protocols since they maintain the routing information before it is needed. Each network node maintains routing information for every other node in the network. Paths generated event information is stored in routing tables and is updated periodically changes the network topology. Many of these routing protocols come from the link-state routing. There are some differences between the protocols that fall into this category depending on the routing information to be updated in each routing table. In addition, these routing protocols maintain different number of tables. The proactive protocols are not suitable for large networks, as they need to maintain node entries for each node in the routing table of each node. This causes more overhead in the routing table resultant consumption of more bandwidth.On demand routing protocols (reactive) These protocols are also called reactive protocols because it does not maintain the routing information or activities of routing in the network nodes if there is no communication . If a node wants to send a packet to another node, then this proto-col in the search for the path of on-demand mode and establishes the connection to transmit and receive the package. The route discovery by flooding the road usually occurs around the request packets network.Destination Sequenced Distance Vector (DSDV) ProtocolThe destination sequenced distance vector routing protocol is a proactive routing protocol is a modification of the conventional Bellman-Ford routing algorithm . This protocol adds a new attribute, sequence number, each entry route table in each node. Routing table is maintained at each node, and with this table, the node transmits packets to other network nodes. This protocol has been motivated by the use of the exchange of data and changing along arbitrary paths of interconnection that may not be close to any Basic description station.Protocol activities and each node in the network maintains routing table for the transmission of packets, and thus connectivity for the various stations of the network. These stations list for all destinations and the number of hops required to reach any destination in the routing table. The routing entry is labeled with a sequence number originated by the destination which is stationary. In order to maintain consistency, each station transmits and updates its routing table periodically. Packets are transmitted between the stations indicate which stations are accessible and how many hops are needed to reach that particular station. Packets can be transmitted containing the layer 2 or layer 3 information is advertised address.Routing transmitting or multicast packets are sent periodically when the nodes move within the network. The DSDV protocol requires each mobile station the network must constantly advertise each of its neighbors, its routing table. Since the entries of the table my change very quickly, the advertising should be frequent to ensure that each node can identify its neighbors in the network. This agreement is placed, to ensure the least number of hops for a route to a destination, and in this way, the node can exchange data, even if there are no direct communication data transmitted by each node will contain the new number link.The sequence and the following information for each new route: - The destination address: the number of hops required to reach the destination-and the new sequence number, originally stamped destinationThe transmitted from the routing table will also contain the address hardware, the network address of the mobile host transmission. The routing tables will contain the sequence number created by the transmitter, and then the newest number of the target sequence is preferred as a basis for making forwarding decisions. This new sequence number is then updated to all hosts on the network can decide on how to maintain the routing entry for that host to the mobile home. After receiving the location information, receiving node increments the metric information and transmits the broadcast. Metric increment is done prior to transmission, because the incoming packet must travel more than one hop to reach its destination. Time between transmission of packets of routing information is another important factor to consider. When the new information is received by the mobile host will soon be retransmitted to make the spread quickly as possible of routing information between all cooperating mobile hosts. The owner of the mobile home as a broken left because they move from one place to another within the network. The broken link can be detected by the layer 2 protocol, which can be described as infinite. When the path is divided into a network, which is then immediately metric assigned infinite metric further extraction that there is not deterministic and the hop sequence number is updated. Sequence numbers from mobile hosts have yet to be defined for the number and sequence of numbers generated to indicate infinite metrics are odd numbers. The reporting in the DSDV protocol has two types Namely: full dump and incremental dump. Transmission takes full dump all routing information, while the incremental dump will only information that has changed since last full dump. Regardless of the two types, transmission is performed in units of data network protocol (NPDU). Full dump requires more NPDU while incremental NPDU requires only one to fit all the information. When packet of information is received from another node, it compares the sequence number with the number of sequence available for that entry. If the sequence number is greater, then it will update the routing information with the sequence number of new otherwise if the information arrives with the same number of sequence appears to the input metric and if the number of jumps is less than the previous item, new information is updated (or if the information is the same metric is more then it will discard the information.) While the information is updated nodes, the metric is increased by 1 and the sequence number is increased even according Similarly, if a new node enters the network, it is announced in the network and the network nodes update their routing information with A new entry for the new node.During broadcasting, mobile hosts want to transmit their routing tables periodically, but due to frequent movements by hosts in the network, this will lead to continuous transmission burst of new routes to each new sequence number from the target. The solution for this is to delay the publication of these lines until it is presented to a Layer2Address metric.Operation best stored in the routing table to the mobile hosts will be equal to the level that uses the DSDV protocol. Layer 3 use addresses of the network layer to the next hop and destination and level 2 will use the MAC address for its operation. One difficulty arising at the operational level 3 and a way must be provided to solve these 3-layer addresses into MAC addresses. Otherwise, resolution of problems as the broadcast address would have been necessary and the loss of bandwidth would be observed. This loss can be substantial because the mechanisms that require retransmission by each mobile node. The solution here is to provide information along with information Layer2 Layer3 Protocol to the second layer functioning Each mobile node would advertise reachability information that destination.Advantages Layer3 protocols DSDV protocol of DSDV guarantees loop-free paths -. Counting to infinity problem is reduced to DSDV -. We can avoid the extra traffic with incremental updates rather than full dump updates - Path Selection DSDV maintains only the best route instead of maintaining multiple paths to each destination .. With this, the amount of space in the routing table is reduced.Limitations of DSDV-waste of bandwidth due to the advertising redundant routing information even if there is no change in network topology -. DSDV does not support multi-path routing -. And Tuesday is my worship to discourage a delay for the advertisement of routes -. And 'cult Tuesday to keep the publicity of the routing table for the larger network. Every host on the network must maintain a routing table for advertising. But the largest network of its lead head, which consumes more bandwidth.Ad-hoc On-Demand Distance Vector (AODV) protocol ProtocolAODV is a very simple, efficient and effective routing for mobile ad hoc networks that have fixed topology . This algorithm has been motivated by the limited bandwidth that is available in the means that are used for wireless communications. It borrows most of the concepts from the DSR and DSDV algorithms advantageous. The on-demand route discovery and maintenance path from DSR and hop-by-hop routing, the use of sequence numbers of the nodes to make the algorithm DSDV cope with topology and routing information. Obtain the paths purely on-demand AODV makes an algorithm veryuseful and desired for MANETs.Working of host AODVEach mobile in the network acts as a router and specialized paths are obtained when required, the network of self-starting Malthus. Each network node maintains a routing table with routing information for the items close of NO, and two separate counters: a node sequence number and a broadcast id. When a node (for example, the source node of 'S') must communicate with another (eg, destination node 'D'), increases its id transmission and initiates path discovery by transmitting a request packet RREQ route toward its neighbors. The RREQ contains the following fields: - source-addr-source-sequence # to maintain freshness information about the path to the source - dest dest-addr-sequence # - specifies the freshness of a route to the destination must be the first. is accepted from the source -. cntThe hop (source-addr, large case-id) pair is used to uniquely identify the RREQ. Then the dynamic plan entry route starts all network nodes that are on the path from S to D. As RREQ travels from node to node, which automatically sets up the reverse path with respect to all these not the source. Each receives any of this package that records the address of the node from which it was received. This is called reverse path setup. The nodes maintain the information for a time sufficient for the RREQ to traverse the network and produce a response to the sender and the time depends on the size of the network. If you do not have a voice of intermediate en route to your destination in its routing table, it compares the sequence number of destination in its routing table to those contained in the RREQ. If the number of target sequence in the routing table is less than that in the RREQ, which retransmits the RREQ to its neighbors. Otherwise, a response packet unicast route to its neighbor, which has received the RREQ What if the same application has not been developed earlier (this is identified using the large case-id and source-addr). Once the RREP is generated, it returns back to the source, based on the reverse path that is fixed in traveled up to this node. As RREP travels to the source, each node along this path set forward a pointer to the node that receives the RREP, and records last sequence number of destination to the required destination. This setup is called the forward path. If in another intermediate node receives RREP after the first multiplication RREP towards it checks for the sequence number of the source destination of the new RREP. The intermediate node updates the routing information and propagates RREP alone again, - If the number of the target sequence is greater than or, if the new sequence number is the same and the hop count is small, OROtherwise, skips only the new RREP. Ensures that this algorithm is loop-free and only the most effective path management table is used.Route Each mobile node in the network maintains a routing table entry for each destination of interest in its routing table. Each entry contains the following information: - Number of the destination next hop destination sequence number of jumps for this active route near-expiry time for the route table information entryThe other useful by the source and destination entries with sequence numbers are called soft state information associated with the entry route. The information about the active neighbors for this route is kept Sun that all active nodes can be notified when a link source along a path to the destination breaks. And the purpose of the request timer expiration time is to eliminate the reverse path routing entries from all nodes that are not active on young AODVThe route.Interesting concepts of concepts that make it desirable AODV MANET with limited bandwidth are as follows: - Minimum space complexity: The algorithm makes sure that the nodes which are not in this active route do not play store the information about the track. After a node receives RREQ and sets a reverse route in its routing table and propagates the RREQ to its neighbors, if not receiving a RREP from its neighbors for this request, removes the routing information that has recorded.Advanced use AODV uses maximum bandwidth: this can be considered the important result of the algorithm. Since the protocol does not need to advertising worldwide periodicals, the consumption of the available bandwidth is less. And a counter of the sequence number is monotonically increase maintained by each node, in order to replace the route cache is not updated. All intermediate nodes in the active route for their routing tables of updating the information to ensure that maximum utilization of bandwidth. Since these routing tables will be used if each intermediate node receives RREQ again from another source to the destination itself. Therefore, any RREPs that are received by the nodes are compared with the RREP that has been propagated with the last, but not the sequence numbers of destination and are deleted if they are better than the already propagated RREPs -. It's easy with a simple act like every doe. a router, Maintaining a simple routing table, and the source node discovery request startup path, making the network self-starting - routing information more effectively: After multiplication in RREP, if a node receives the RREP is less hop-count, it updates its routing information with this best path and propagates - Most current routing. Info: The path information is obtained on request. Thus, after which propagates in RREP, if not de Receives RREP located at the destination with the highest number of sequence, updates its routing information with this last path and propagates -. Loop-free routes The algorithm maintains loop free paths with the simple method. logic nodes for better discarding packets non-broadcast the same id - Coping Up with dynamic topology and broken links: When the nodes move from their seats and the topology is changed or left in the active route is broken, the intermediate packet node discovers the fracture propagates RERR link. And the source node re-initializes the discovery path if the path still desired. This ensures a rapid response to broken links -. Highly scalable The algorithm is highly scalable because of the complexity minimum space avoided and when transmitting Compared DSDV.Advanced uses of AODV-Due to its reactive nature, capable of managing AODV dynamic behavior. Vehicle ad hoc networks - Used for both unicast and multicast using the 'J' (join the multicast group) flag in packets.Limitations and disadvantages of AODV need the means of transmission: The algorithm provides / requires that the no of in transmission medium can detect their transmissions - the generals on the width of the head on the width of banda banda will occur compared to DSR, when RREQ travels from node to node in the production process of discovering the route information on request, it sets the opposite. path in itself, with the addresses of all the no-through which is passing all this information and it brings everything his way - No re-use AODV routing technique lacks efficient path maintenance .. Routing information is always obtained on request, also for traffic in the common case - It is vulnerable to misuse Messages can be used to insider attacks including disruption path, on the invasion, node isolation, and the consumption of resources -. AODV lacks support for high. throughput metric routing: AODV is designed to support the shortest hop count metric. This metric favors long, low bandwidth left over, short, high-bandwidth link -. High latency route discovery reactive AODV is a routing protocol. This means that AODV does not discover a path to flow started. This latency discovery path can be the result of a high content of large-scale ConclusionDiscussionAfter mesh networks.Discussion and revise the concept of the ad hoc wireless networks and two routing protocols is to say, AODV and DSDV. We would like to make a comparative discussion of both protocols with their pros and cons. Most of this discussion is based on previous studies and implementations -. DSDV is a proactive routing proto-col, each node maintains routes to the network, while AODV is a reactive routing protocol that finds the path on request or when the path is necessary -. Broadcasting in DSDV is done periodically to maintain routing updates and AODV, only hello messages are propagated to its neighbors to maintain local connectivity -. DSDV routing algorithm maintains a concept of sequence number to update the latest information for a path. Also, the same concept is adapted from AODV routing protocol -. Because of regular updates on the air in DSDV, bandwidth is wasted when the no of stationary. However, this is not the case with AODV, as it propagates only the hello messages its neighbors -. To send data to a particular destination, there is no need to find a path such as DSDV routing protocol maintains all routes in the routing tables for each node. While AODV must find a path before sending a given -. Overhead in DSDV is more when the network is large and it becomes difficult to maintain routing tables at each node. But, in the lead is less than AODV in that it maintains tables to maintain local connectivity -. DSDV can not handle high-speed mobility due to the lack of alternative routes and then routes the routing table is stale. While in AODV this is the other way, how to find routes on demand -. Comparatively DSDV throughput decreases as it needs to advertise regular updates and upgrades even-driven. If the node mobility is high then the occurrence of event-driven updates are. But not advertise in all the AODV routing updates and then the volume is stable.ConclusionThe study reveals that, DSDV routing protocol uses more bandwidth, due to the frequent dissemination of routing updates. While the AODV is better than DSDV since it does not maintain the routing tables of the nodes which results in less overhead and more bandwidth. From the above, it can be assumed that DSDV routing protocols works best for smaller networks, but not for large networks. So, my conclusion is that AODV routing protocol is best suited for general mobile ad hoc networks which uses less bandwidth and lower costs compared to DSDV routing protocol. [ABSTRACT] Mobile ad-hoc NetworksAn ad hoc network is a collection of wireless mobile hosts forming a temporary network to organize without the help of any stand-alone or centralized infrastructure administration.Mobile ad hoc networks themselves and themselves configure networks wireless multihop, where the changes, the structure of the network dynamically. This is mainly due to the mobility of the nodes [8]. The nodes of these networks use the same random access wireless channel, is cooperating in a friendly way to be involved in multi-hop routing. The nodes of the network not only as a host, but also as a router, the data of the cycle to / from another network node. In mobile ad hoc networks, where there is no support infrastructure, as is the case with wireless networks, and may for purposes not de out of reach of a source node sending packets, a process of routing is always necessary to find a solution so that packets matching between the source and destination. Within a cell, a base station to reach all the mobile nodes without routing via the transmission common wireless networks. In the case of ad-hoc networks, each node must be able to transmit data to other nodes. This creates additional problems with the problems of dynamic topology that changes in unpredictable connectivity • routing problems in mobile ad hoc net-works-asymmetric links. Most of the wired networks rely upon the symmetrical compounds, which are always fixed. But this is not a case of ad hoc networks, as nodes are mobile and constantly changing their position within the network. For example, consider a MANET (Mobile Ad-hoc network), where the node B sends a signal to node A, but that says nothing about the quality of the connection in the opposite direction - head routing. In ad hoc wireless networks, do not often change their position within the network. . So, some old routes in the routing table, the unnecessary overhead of routing leads generated - Interference: This is the main problem in mobile ad hoc networks, such as links and are always going to the transmission properties, could be a transmission interfere with one another and can not hear a transmission from other nodes and can damage the entire transmission - dynamic topology. This is also the main problem with the ad hoc routing, since the topology is not constant. The mobile node can move to medium can change the properties. In ad hoc networks, routing tables must somehow reject these changes in the topology and routing algorithms must be adapted. For example, in a fixed network routing table update is performed for every 30 sec. The refresh rate can be very low for ad hoc networks. • Classification of routing protocols in MANET'sClassification of Manet routing protocols can be done in many ways, but most of them are running routing strategy and network structure. According to the strategy of routing, routing protocols can be used as a table-driven and source initiated classified, depending on the structure during a network that supports routing, hierarchical routing and routing classified location. Both the table-driven protocols initiated and the source under the flat routing.Table-driven routing protocols (active), these protocols will be called proactive protocols, since it is the routing information before it is required to maintain. Each network node maintains routing information to all other nodes of the network. Route information is usually kept in the routing tables are periodically updated and changes to network topology. Many of these routing protocols are provided by the link-state routing. There are some differences between the protocols that fall into this category depending on the routing information, and updated in each routing table. In addition, maintaining these routing protocols variable number of tables. The active protocols are not suitable for large networks, as they did with the node entries for each node in the routing table maintained by each node. This causes mentioned more in the head in the routing table to be consumed more bandwidth.On demand routing protocols (reaction) These protocols and protocols as reagents do not maintain the routing information routing or activity in the nodes of the network when there is no communication. When a node wants to send a packet to another node, then this path with the proto-type studied in a request and the connection to the transmission and reception of the package. The route discovery typically occurs, flooding the route request packets in network.Destination sequenced distance vector (DSDV) ProtocolThe goal sequenced distance vector routing protocol is a proactive routing protocol, which is a modification of the traditional Bellman-Ford algorithm routing. This protocol is a new attribute, sequence number, with each entry route table in each node. Routing table each node, and this table holds the node transmits packets to other nodes in the network. This protocol is the change to the use of the data exchange arbitrary paths and pushes the compound that can not station.Protocol in the vicinity of an overview arbitrary base conducts each node in the routing table of the network for the transmission of packets, and also for connectivity at various stations of the network. These stations list for all destinations and the number of hops required to reach any destination in the routing table. The routing entry with a sequence number that has been created by the destination station is marked. To maintain consistency, each station transmits and updates its routing table at regular intervals. The packets that specify transmission between the stations, the stations are accessible and how many hops are needed to reach this particular station. Packets can be transmitted, the Layer 2 or Layer 3 information address.Routing broadcasting or multicast packets at regular intervals, as if the nodes are moving in the transfer of the network will be advertised. The DSDV protocol requires each mobile station the network must constantly advertise to each of its neighbors, its routing table. Since the entries in the table to change my very fast, the advertising should be done frequently to ensure that each node is its neighbor to look in the network. This agreement is prepared to guarantee the least number of hops for a path to a destination, in this way, the node can exchange data, though it may be no direct connection to be sent from each node containing the new sequence number and the following information for each new route are: - The destination address, the number of hops required to reach the goal and the new sequence number, which originally contained destinationThe transferred from the routing tables and hardware address, address Network brand mobile host to be transmitted to reach. The routing tables are generated sequence number of the transmitter and then the new number of the target sequence is preferred as a basis for forwarding decisions. This new sequence number is updated on all other computers on the network, how can you determine the routing entry for the originating host cell to maintain. After receiving the location information receiving node increases the value of metrics and transmits information via radio. Increase Metric is made before the transfer, because the incoming packet has to travel another hop to reach their goal. The time between sending packets of information routing is another important factor to consider. If the new information is received from the mobile host, will be retransmitted as soon as possible to make the rapid dissemination of routing information among all mobile hosts cooperating. The mobile host can result in broken links as they move from place to place to place within the network. The broken link can be recognized by the layer 2 protocol that can be described as infinite. If the path is divided into a network, then once that there is an infinite metric metric by determining that it is not assigned a hop and the sequence number of updated. Sequence numbers that are used by mobile hosts to the number of defined rights and generates the sequence numbers to indicate parameters endless odd numbers. The transmission of information in the protocol DSDV is of two types, namely: full dump and incremental discharge. Full dump will broadcast the entire routing information, while the incremental dump will bring the only information that has been modified since the last full dump. Regardless of the two types of radio network in protocol data units (NPDU) is made. Full dump requires more NPDU required during the incremental fit only NPDU information. If a packet of information is received from another node, it compares the sequence number with the number of sequence available for this entry. If the sequence number is greater, then the routing information with the sequence number of new update other if the information arrives with the same number of sequence appears to the input metric and if the number of jumps is lower than the previous input of the new information is updated (when information must be equal or more metric, then discard the information). While the information on the node is updated, the metric is incremented by 1 and the sequence number is increased even 2. Similarly, when a new node enters the network, will be announced on the network and the network nodes update their routing information with a new voice for radio node.During new mobile hosts in their routing tables regular intervals, but due to transfer to the frequent movement of the networks will bring guests to the memory buffer for new transmission lines for each new sequence number of that goal. The solution is to delay the advertising on such lines up shows a better metric.Operation Layer2Address in the routing table stored at the mobile hosts, so as to correspond to the layer, which is operated on the protocol DSDV,. Layer 3 addresses of the network layer are used for the next hop and destination addresses and address Layer 2 MAC to use the use for their operation. One difficulty is created in the layer-3 operations, and provide an opportunity to address this level 3 MAC addresses are resolved. Otherwise, problems such as the broadcast address resolution would have been necessary, and the loss of bandwidth would be observed. This loss may be significant, since these mechanisms require the further spread of each mobile node. The solution is here for layer 3 protocol information along with information from Layer 2 to Layer 2 mode. Would advertise each mobile node, ensuring accessibility, information on Layer 3 protocols that the proto-col DSDV destination.Advantages DSDV path without loops -. Counting to infinity problem is reduced in DSDV -. We can avoid the additional traffic with incremental updates rather than full update dump - Path Selection. DSDV maintains only the best way, instead of many paths to each destination. Therefore, the amount of space in the routing table reduced.Limitations DSDV-bandwidth consumption due to unnecessary advertising of routing information, even if there is no change in the network topology -. DSDV does not support multi-path routing -. It is cult to determine a time delay for the display of routes -. E 'of worship to the routing table for the largest advertising network to maintain. Every host on the network must maintain a routing table for advertising. But for a larger network that would be in the lead, more bandwidth.Ad-hoc On-Demand Distance Vector (AODV) routing protocol ProtocolAODV a very simple, efficient and effective system for mobile ad hoc networks, the topology is fixed on any lead consumed. This algorithm has been motivated by the limited bandwidth available, which is in the means which are used for wireless communication. He borrows the most beneficial concepts from DSR and DSDV algorithm. The demand for discovery and route maintenance and route of DSR hop-by-hop routing, nodes make use of sequence numbers from DSDV algorithm to cope with the topology and routing information. Obtain the tracks purely on-demand AODV makes an algorithm veryuseful and desired for AODVEach MANETs.Working of portable computers in the network acts as a router specialized, and receive paths, depending on the case, making the network itself off. Each node of the network maintains a routing table with the routing information added to the non-adjacent, and two separate counters: a sequence number and a node ID of transmission. When a node (eg, 'S' the source node) with another (for example, the destination node 'D') to communicate is increased, its ID and transmission begins the discovery route by sending a request packet Via RREQ to its neighbors. The RREQ contains the following fields: -. To obtain source-addr source-to-order freshness # path information to the source - dest dest-addr-sequence # - Indicates the freshness of a route to the destination must be before it is accepted from the source -. Hop-cntThe (source addr, large case-ID) pair is used to uniquely identify the RREQ. Then the dynamic routing table entry starts the device on all nodes of the network, on the way from S to D As RREQ travels from node to node, it is automatically the return of all this back to the source. In each of receiving this package records the address of the node from which it was received. This is called reverse path setup. The nodes maintain this information to allow time for the RREQ to traverse the network and produce a response to the sender and depends on the size of the network. If an intermediate layer has not entered en route to your destination in its routing table, it compares the sequence number of destination in its routing table to those contained in the RREQ. If the number of target sequence in the routing table smaller than that of the RREQ, it repeats the RREQ to its neighbors. Otherwise, a unicast route reply packet to its neighbor with which the RREQ was received when the same request was not processed before (this will be the basis of extensive case ID and source address). Once the RREP is generated, moves back to the source, based on the reverse way, that is set up went to this node. As RREP travels to the source, each node on this path is a forward pointer to the node from which it receives the RREP, and stores the current number of target sequence on the target application. This is known as the setting of the forward path. When an intermediate node RREP further obtained according to the propagation of the first RREP towards the source for controlling the number of target sequence of the new RREP. The intermediate node updates the routing information and propagates RREP new only - If the number of the target sequence is greater, or if the sequence number of the new and the same number of hops is small, OROtherwise, it is easy to skip the RREP again. This ensures that the algorithm is loop-free, and only the most effective way used.Route management table Each mobile node in the network maintains a routing table entry for each target of interest in its routing table. Each entry contains the following information: - next destination hop count hop active neighbors Destination Sequence number for the travel time of the deadline for the information of the route table in entryThe other useful items, along with the sequence numbers of origin and destination assigned is contained, soft-state information means the voice is broken. The information about the active neighbors for this route will be maintained, so that all active source nodes are notified when a link breaks along a path to the destination. And the purpose of the timer timeout path request is in the opposite direction by routing messages from all the nodes which are not active on the concepts of route.Interesting AODVThe concepts of AODV which are desirable for MANET with limited bandwidth, the following, clean: - minimum space complexity: The algorithm ensures that nodes do not speak to the current route is no information about the trail. After a node receives the RREQ and sets a reverse route in its routing table and propagates the RREQ to its neighbors, if you do not receive RREP from its neighbor for that request, removes the routing information using recorded.Advanced maximum use of bandwidth AODV: This can be considered the great success of the algorithm. Since the protocol does not require periodic global advertising, the demand for lower bandwidth available. It is a monotonically increasing sequence number counter is maintained by each node to replace the stale routes stored in cache. All intermediate nodes in an active route update their routing tables also ensure maximum use of the bandwidth. Since these routing tables will be repeated if the intermediate node receives RREQ from any other source for the same objective. In addition, all RREPs received by the node, propagate the RREP with the last use of numbers of the target sequence and are deleted when they are not better than what has already been touted RREPs be compared - Simple. It 'easy to do with anyone without us, as a router, while maintaining a simple routing table, and the source node to initiate the request for the search path, the network itself - the routing information itself. After the delivery of a RREP, if a node receives a RREP is the hop count is smaller than its updated routing information and propagates in this way - the latest routing information. The path information if necessary. Even after the spreading of a RREP, if not a de finds a RREP becomes larger with the number of target sequence, updates its routing information with the last track and propagates - loop-free routes. The algorithm maintains loop-free paths through the simple logic of the node does not discard more packets for the same broadcast ID - Dealing with dynamic topology and broken links. If the node is changed from their seats and network topology or link in the active route is broken, the intermediate nodes that discovered this link RERR packet propagates a fraction. And the source node initiates the route discovery, if you like, or the path. This ensures a quick response for broken links - high scalability. The algorithm is highly scalable, can be avoided when used with the DSDV.Advanced the minimum space requirements and complexity of the programs due to its reactive nature of AODV, AODV able to manage the dynamic behavior of the vehicle relative to networks hoc, both for unicast and multicast with the "J" (join multicast group) were used in the packets.Limitations flag and disadvantages of AODV request to transmit the media. The algorithm is expected / not required to recognize each other in the middle of transmission of their programs "- overhead on the bandwidth overhead in bandwidth compared to the DSR, when a RREQ travels from node to node in the CESS Pro discovery of the route information on request, must be performed in the opposite direction into itself with the addresses of all matter that passes through, and carries out all this information to his whole way - no re-routing information: .. AODV lacks an efficient equipment for road maintenance, the routing information is always available on demand, among other traffic common case - is vulnerable to abuse: Messages can be collected and used for internal attacks, including path interference, encroachment on, ground loop isolation and consumption of resources. be - no support for high-throughput routing metrics AODV: AODV is designed to support ... the shortest hop count metric This metric is long, low-bandwidth connections favored over short and broadband connections - High latency discovery is a reactive path AODV routing protocol. This means that AODV does not discover a path which is brought into a river. This latency discovery path can lead to large mesh in height and ConclusionDiscussionAfter networks.Discussion revision of the concept of wireless networks and ad hoc two routing protocols .., ie AODV and DSDV We want to make a comparative discussion of the two protocols with their advantages and disadvantages of most of the discussion will be based on previous studies and implementations -. DSDV is a proactive routing proto-col, the path maintains at each node of the network, while a reactive AODV routing protocol that finds the path, if necessary or if the path is necessary, - .. DSDV routing algorithm maintains a concept sequence number to update the latest information on a Route - Broadcasting will receive periodic updates in DSDV and AODV routing, hello messages are sent to the neighbors, do to maintain the local connectivity is also the same concept of custom routing protocol AODV - .. Because of regular updates DSDV sent, the bandwidth is wasted if non-stationary, but this is not the case with AODV, because only the hello messages sent to its neighbors - .. to send data to a particular destination, it is not necessary to find a path, such as DSDV routing protocol keeps all the routes in the routing tables, while for each node, AODV has to find a path before sending a data set - .. DSDV overhead is more if the network is large and it is difficult, the routing tables to arrive at each node keeps in mind But AODV significantly lower, as there are tables to maintain the local connectivity to keep - .. can not deal DSDV mobility at high speed due to lack of alternative routes, so. routes in the routing table is stale while in AODV this is the other way, as he found the route on request - .. The speed is reduced comparatively DSDV as it needs to advertise regular updates and even-driven updates, if the node mobility is high then the occurrence of event-driven updates. But do not advertise any AODV routing updates, and so the study shows that stable.ConclusionThe speed DSDV routing protocol consumes more bandwidth for frequent transmission of routing updates. While AODV is better than DSDV because it does not matter that the routing tables of nodes, leading to a lower load and higher bandwidth. From the foregoing it can be assumed that DSDV routing protocols work best for smaller networks, but not for large networks. Thus, my conclusion that AODV routing protocol is more suitable for general mobile ad hoc networks, as it uses less bandwidth and less overhead than DSDV routing protocol.