# Introduction obile Adhoc Networks are created for temporary time where nodes can join and leave the created network without any restriction [1]- [3]. Nodes can communicate and route the data in any direction. Nodes which configured themself with MANET environment may be part of small network or may be part of large network. In MANET type of communication is peer to peer. Peer to Peer networks are "peers" of computers which are connected with each other with the help of Internet and P2P software. Systems in P2P environment act as a client and server by itself. Main Challenging part of Mobile Adhoc Network is maintaining the routing information without losing it. Because nodes are arbitrary moving in Manet so required routing protocols which manage the route information in there table if particular node switch off from the Mobile Adhoc Network. Generation of error message should be there if communication link is broken between the nodes when they leave and join the selected network. # II. The Classification Of Routing Protocols For this purpose routing protocols can be classified as described below: a) Proactive Routing / Table Driven These types of routing protocols maintains the list all the routes from source to destination in advance [2]. These types of protocols maintain fresh lists of routes by periodically distributing routing information throughout the network. b) Reactive ( On -Demand) Routing These types of protocols find a route on demand by flooding the network with "Route Request" packets [2]. c) Hybrid (both pro-active and reactive) Routing Reactive These types of routing protocols combine the advantages of proactive and reactive routing [3]. The routing is initially established with some proactively prospected routes and then serves the demand of additionally activated nodes through reactive flooding. The choice for one or the other methods requires predetermination for typical cases. To transfer data from one node to another node we need some routing protocols that will transfer data without any loss. Protocols are set of rules and regulations which are used in network communication. different paths are for each hop stored in routing tables in advance .When ever source want to send data to destination. In will search the path from the routing tables [1]- [3]. In DSDV each routing table contains the Hop count and Sequence Number. Hop count tells the number of hops occurs in the path for source to destination. Sequence Number is used to update path. The path with the old sequence number is replaced with the new sequence number. The New Sequence number defines the new path from source to destination. FSR is proactive and flat routing protocol. It is also known as Link State Routing Protocol because it uses topology information from source to destination for sending the data [15]. Link state defines the activeness of nodes while creations of path from source to destination. Inactive nodes are not part of the path .FSR also maintain the information about the nodes which are near to the focal point. To maintain the topology information WRP uses Link State Table. TORA is reactive protocol and on demand routing protocol [3]. It is also known as Link reversal routing protocol. Path searching is based on the source initiation. In the TORA, the path search is performed from higher level to low level. Each node maintains multiple paths from source to destination. While transferring the data from source to destination ,any path can be used, which is currently available for transfer the data. Shortest path method is not applicable in TORA. It The AODV routing protocol is an on demand routing protocol [8]. Therefore, routes are created only when the requirement is generated [2]. "Hello Messages" may be used to detect and monitor neighbors. Periodically nodes broadcast the "Hello Message" to determine the activeness of neighbor nodes [6]- [9]. This technique is used to know the status of active nodes for data transfer. It broadcasts a "Route Request" (RREQ) to each intermediate node. if the receiving node does not receive RREQ and there is no route to the destination rebroadcasts the RREQ. If the receiving node is the destination or has a current route to the destination, it generates a Route Reply (RREP). i. Advantages 1. The searching of paths are done when the requirement is generated. ii. Disadvantages 1. Multiple route replies are generated for the same route request. 2. Time to time "hello" message is generated; which is wastage of resources like battery consumption. c) Distance Source Routing Protocols (DSR) DSR is an on demand based routing protocol that is based on source routing [2]. It is designed for use in multi-hop wireless adhoc networks of mobile nodes. DSR is based on the concept of "Route Discovery" and "Route Maintenance". In DSR the Route Discovery process is started by a packet that discovers the path from source to destination and accumulates the whole information about path into its header [2]. Route Reply is generated by the destination if the route is discovered from source to destination and If no path is found from source to destination then the error message is generated [2], [10]. i. Advantages 1. When the whole path is searched from source to destination, then reply is sent back to source. One source reply is generated for route request. 2. It is source generated type of routing protocol. 3. No beaconing technique is used. ii. Disadvantages 1. Protocol is unable to find the broken links. 2. Full path searching is time consuming process. # d) Zone Routing Protocols (ZRP) ZRP is hybrid protocol as it is combination of reactive and proactive [12]. Reactive Protocol is on demand protocol which finds the path from source to destination when requirement is generated. Proactive protocol means that information about each path is already stored in the tables. Based on zones, ZRP can also be divided into Intra Zone Routing Protocol (IARP) and Inter Zone Routing Protocol (IERP). i. Advantages 1. It is combination of reactive and proactive. # If the nodes are within the zone table driven technique is used, if nodes are far from zone reactive path searching technique is used. ii. Disadvantages 1. If the zones are overlapping, difficulty is in the path search. V. # Metrics in Manet Metrics are measurements in the manet used to analysis the performance of routing protocols. Metrics are required to evaluate the performance of network; metrics defines how well the network is doing under different parameters [16]. The metrics can be classified in two parts. # Conclusion In this paper, we have surveyed the various routing protocols with their advantage and disadvantages. We analyzed the metrics which are used to analysis the performance of the network. As mobile adhoc network growing day by day. there are many area to review like routing protocols, types of attack, application, IDS etc. 11![Figure 1 : Classification of Manet Routing Protocols III. Proactive Routing Protocols a) Distance Source Initiated Vector (DSDV)DSDV is table driven and source initiated routing protocols. In DSDV the information about](image-2.png "Figure 1 : 1 Global") 1![Applicable Large type of Networks. 2. Nodes are excluded in the routing tables which are not currently working. ii. Disadvantages 1. Maintaining the topological information about nodes is difficulty which is far from the focal point. 2. It is wired routing protocols. a) Temporary Ordered Routing Protocols (TORA)](image-3.png "i. Advantages 1 .") i. Advantages1. The Updation in routing tables regarding paths isdone time to time by broadcasting of messagesbetween the hops.2. Paths are predetermined.ii. Disadvantages1. Not applicable for Large Networks.2. Wastage of battery resources unnecessarily dueto updation of paths.i. Advantages1. It stores the information about previous node andnext node in the Routing Table.2. Path searching and path updation cost is less.ii. Disadvantages1. Required more space due to multiple tables.2. Complexity is increases due to creation ofshortest path in advance and storing the previousnode and next node information in the RoutingTable3. Multiple Updation in multiple tables requires morepower consumption.c) Fisheye State Routing Protocols (FSR)b) Wireless Routing Protocols (WRP)WRP is table driven or proactive routing protocol[2]. i. Advantages1. Multiple paths available from source todestination.2. Efficient and loop free routing.3. Overhead reduce because of on demandcreations of routes.ii. Disadvantages1. Non availability of paths when required.2. Delay in the path searching.3. Flooding of messages in the network whilediscovering of routes on demand.b) Adhoc on Demand Distance Vector RoutingProtocols (AODV) © 2015 Global Journals Inc. (US) The Literature Survey on Manet, Routing Protocols and Metrics * Rfc for Mobile Ad hoc Networks (MANET) 1997 * International Journal Personal Metrics Formula Throughput No. of packet received/No. of per Unit of time PDR No. of packet received/No. of packet sent End to End Delay Time the pkt sent-Time the pkt received Jitter ElizabethMRoyer PA+1)-(PS+1))-((PA)-(PS)))/N-1 1999 A Review of Current Routing Protocols for Adhoc Mobile Wireless Networks * Packet Loss No. of pkt sent-No..of pkt received PA=Packet Arrival, PS=Packet Start Communication IEEE Computer Society 6 * Manet Routing Protocols Taxonomy HNagham Saeed FMaysam Abbod Ai-RaweshidHameed Proc. of International Conference Future Communication Networks (ICFCN) of International Conference Future Communication Networks (ICFCN) IEEE Computer Society 2012 * Investigate the Performance metrics of Mobile Adhoc Networks (MANET) NorsuzilaYaaco NurhazwaniRosli International Symposium Wireless Technology and Application (ISWTA) Mohd TarmiziAzita Laily Yusof Ali IEEE Computer Society 2013 * Ad-hoc On-Demand Distance Vector Routing CEPerkins EMRoyer Proc. of 2nd International Conference on Mobile Computing System and Applications of 2nd International Conference on Mobile Computing System and ApplicationsNew Orleans, LA IEEE Computer Society 1999 * An Implementation Study of the AODV Routing Protocol ElizabethMRoyer CharlesEPerkins Proc. of International Conference on Wireless Communication and Networking of International Conference on Wireless Communication and Networking 2000 * Rfc for Adhoc on Demanding Routing Protocol * Research and Improvement of AODV Protocol in Adhoc Network Jiao Wen-Cheng Jing Zheng Proc. of 6th International Conference on Wireless Communications Networking and Mobile Computing (WiCOM) of 6th International Conference on Wireless Communications Networking and Mobile Computing (WiCOM) IEEE Computer Society 2010 * MAODV: Modified Wormhole Detection AODV Protocols UmeshKumar Chaurasi MrsVarsha Singh Proc. of 6th International Conference on Contemporary Computing (IC3) of 6th International Conference on Contemporary Computing (IC3) IEEE Computer Society 2013 * Rfc for Dynamic Source Routing * A Validation Model for the DSR Protocol AnaCavalli CyrilGrepet StephaneMaag VincentTortajada Proc. of 24th International Conference on Distributed Computing of 24th International Conference on Distributed Computing IEEE Computer Society 2004 * Rfc for Zone Routing Protocols * Scalable Unidirectional Routing with Zone Routing Protocol (ZRP) Extensions for Mobile Ad-Hoc Networks PrasunSinha VSrikanth SonKrishnamurthy Dao Proc. of International Conference on Wireless Communications and Networking of International Conference on Wireless Communications and Networking 2000 3 * Scalable Unidirectional Routing with Zone Routing Protocol (ZRP) Extensions for Mobile Ad-Hoc Networks PrasunSinha VSrikanth SonKrishnamurthy Dao Proc. of International Conference on Wireless Communications and Networking of International Conference on Wireless Communications and Networking 2000 3 * Rfc for Fisheye State Routing Protocols * Rfc for Routing Protocol Performance Issues andEvaluationConsiderations