A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs <s> Offline Optimal Routing (MANUAL). <s> An ad-hoc network is the cooperative engagement of a collection of mobile nodes without the required intervention of any centralized access point or existing infrastructure. We present Ad-hoc On Demand Distance Vector Routing (AODV), a novel algorithm for the operation of such ad-hoc networks. Each mobile host operates as a specialized router, and routes are obtained as needed (i.e., on-demand) with little or no reliance on periodic advertisements. Our new routing algorithm is quite suitable for a dynamic self starting network, as required by users wishing to utilize ad-hoc networks. AODV provides loop-free routes even while repairing broken links. Because the protocol does not require global periodic routing advertisements, the demand on the overall bandwidth available to the mobile nodes is substantially less than in those protocols that do necessitate such advertisements. Nevertheless we can still maintain most of the advantages of basic distance vector routing mechanisms. We show that our algorithm scales to large populations of mobile nodes wishing to form ad-hoc networks. We also include an evaluation methodology and simulation results to verify the operation of our algorithm. <s> BIB001 </s> A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs <s> Offline Optimal Routing (MANUAL). <s> Little attention has been given to understanding the fault recovery characteristics and performance tuning of native IP multicast networks. This paper focuses on the interactions of the component protocols to understand their behavior in network failure and recovery scenarios. We consider a multicast environment based on the Protocol Independent Multicast (PIM) routing protocol, the Internet Group Management Protocol (IGMP) and the Open Shortest Path First (OSPF) protocol. Analytical models are presented to describe the interplay of all of these protocols in various multicast channel recovery scenarios. Quantitative results for the recovery time of IP multicast channels are given as references for network configurations, and protocol development. Simulation models are developed using the OPNET simulation tool to measure the fault recovery time and the associated protocol control overhead, and study the influence of important protocol parameters. A testbed with five Cisco routers is configured with PIM, OSPF, and IGMP to measure the multicast channel failure and recovery times for a variety of different link and router failures. In general, the failure recovery is found to be lightweight in term of control overhead and recovery time. Failure recovery time in a WAN is found to be dominated by the unicast protocol recovery process. Failure recovery in a LAN is more complex, and strongly influenced by protocol interaction and implementation specifics. Suggestion for improvement of the failure recovery time via protocol enhancements, parameter tuning, and network configuration are provided. <s> BIB002 </s> A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs <s> Offline Optimal Routing (MANUAL). <s> In this paper we propose and discuss an optimized link state routing protocol, named OLSR, for mobile wireless networks. The protocol is based on the link state algorithm and it is proactive (or table-driven) in nature. It employs periodic exchange of messages to maintain topology information of the network at each node. OLSR is an optimization over a pure link state protocol as it compacts the size of information sent in the messages, and furthermore, reduces the number of retransmissions to flood these messages in an entire network. For this purpose, the protocol uses the multipoint relaying technique to efficiently and economically flood its control messages. It provides optimal routes in terms of number of hops, which are immediately available when needed. The proposed protocol is best suitable for large and dense ad hoc networks. <s> BIB003 </s> A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs <s> Offline Optimal Routing (MANUAL). <s> Incorporating multi-hop ad hoc wireless networks in theIP infrastructure is an effort to which a growing communityparticipates. One instance of such activity is theextension of the most widely deployed interior gatewayrouting protocol on the Internet, OSPF (Open Shortest PathFirst), for operation on Mobile Ad hoc Networks (MANETs).Such extension allows OSPF to work on heterogeneousnetworks encompassing both wired and wireless routers,which may self-organize as multi-hop wireless subnetworks,and be mobile. Three solutions have been proposed for thisextension, among which two based on techniques derivedfrom multi-point relaying (MPR). This paper analyzes thesetwo approaches and identifies some fundamental discussionitems that pertain to adapting OSPF mechanisms to multihopwireless networking, before concluding with a proposalfor a unique, merged solution based on this analysis. <s> BIB004 </s> A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs <s> Offline Optimal Routing (MANUAL). <s> In this paper, we investigate the benefits and tradeoffs among various routing strategies used in Mobile Ad Hoc Networks (MANET). In particular, we compare the performance of OSPF-MDR, OLSR, and Composite Routing. Our composite routing implementation is based on further extensions of OSPF-MDR that employs OLSR as the sub-IP MANET routing protocol. The performance evaluation was conducted on an emulation test-bed that utilizes the light-weight Linux network stack virtualization, namely network namespaces. The performance results show that OLSR outperforms OSPF-MDR. As a result, composite routing can leverage OLSR to achieve better network performance than OSPF-MDR with less overhead. Furthermore, composite routing can significantly reduce routing updates to legacy networks due to MANET dynamics (by about 95% under high mobility). <s> BIB005 </s> A Survey on Investigating the Need for Intelligent Power-Aware Load Balanced Routing Protocols for Handling Critical Links in MANETs <s> Offline Optimal Routing (MANUAL). <s> We provide a comparative analysis of various routing strategies that affect the end-to-end performance in wireless mesh networks. We first improve well-known link quality metrics and routing algorithms to enhance performance in wireless mesh environments. We then investigate the route optimality, i.e., whether the best end-to-end route with respect to a given link quality metric is established, and its impact on the network performance. Network topologies, number of concurrent flows, and interference types are varied in our evaluation and we find that a non-optimal route is often established because of the routing protocol's misbehavior, inaccurate link metric design, interflow interference, and their interplay. Through extensive simulation analysis, we present insights on how to design wireless link metrics and routing algorithms to enhance the network capacity and provide reliable connectivity. <s> BIB006
This routing is partially constructed by the network administrators. In this routing, the optimality depends on the reference route set initially with respect to meeting several link quality criteria, determined by link metrics. This reference route needs to be optimal for the rest of the routing decisions to be optimal. Prior to the start of an active data session, every node collects the required link metric information over all the neighbouring links. With this information a node runs Dijkstra's algorithm to find the optimal route toward all destination nodes. A source node after knowing the optimal route compares the end-to-end metrics and selects the optimal path with the best end-to-end metric BIB006 . This protocol is proposed for wireless mesh networks; however, it may be applicable to MANETs also. The issue lies in establishing the reference route for MANETs. Intelligent load balanced routing protocols which learn quickly the nearoptimal routes based on the traffic towards destination would be of much use. BIB003 and AODV BIB001 . However, these mobile-only protocols attempt to divide a network where clear divisions no longer exist. The open shortest path first (OSPF) routing algorithm is a wired protocol that represents a good candidate to extend to support MANETs. OSPF has various features like support to multicast routing, multiple same-cost paths, and the ability to organize a network as a hierarchy BIB002 . OSPF protocol is destined principally for wired networks. Therefore, it works well with predictable topology changes under reliable medium. But these will not hold for highly dynamic and unpredictable MANET. The reason is that the nodes in a MANET tend to form peer relationships as they come into contact at random. This results in altering link state information, which will not be suitable for OSPF routing. In addition, frequent packet loss exists due to path loss, interference, noise, shadowing, and multipath. Therefore, OSPF needs to be modified to meet the routing requirements of MANETs. This includes modifying the protocol to adapt to topology changes, minimizing data exchange for link state advertisements and control overhead BIB005 . Also, OSPF uses a link-state routing approach to find the least-cost path from a source router to destination routers within a group of routers. This exchange of routing information is called flooding. By flooding, at the expense of overhead, the routers are able to obtain a complete view of the network topology. The data exchanges are for advertising the state of links, missing as well as altered. This link state information is stored in link state database (LSDB). This database has the complete picture of the network topology and, therefore, is used as input to apply Dijkstra's algorithm for finding least cost paths from the routes to the other nodes which might become the chosen destinations. Since every router is associated with LSDB, there has to be a synchrony between LSDB of every router. This is done via periodic route broadcasts about the current state of links from every router. In OSPF, the idea of designated router (DR) is extended for MANETs as MANET designated router (MDR) as a measure to reduce flooding overhead. Cisco's OSPF extension uses smart peer identification to handle the packets to reduce flooding overhead. This smart peer technique estimates a mobile node to be smart if it responds to a hello message within a marked/short span of time. For nodes which do not respond at the earliest, the size of hello message is reduced for the next round of hello message. This protocol is called incremental hello protocol. A better modification is OSPF multipoint relaying (MPR) which uses an MPR selector set to reduce adjacent nodes for which messages are broadcasted. Reportedly this modification of OSPF is the most advantageous in terms of reduction in flooding overhead BIB004 .