Local restoration algorithm for link-state routing protocols

Link-state protocols such as OSPF are the dominant routing technology in today’s Internet. Despite their many advantages, these protocols require the flooding of new information across the entire routing area after changes in any link state (e.g. link failures). As the routing area grows or the frequency of link-state changes increases, the overhead (in terms of bandwidth and processing cost) of flooding becomes prohibitive. Furthermore, such flooding over a large area will cause temporary inconsistency of link states among many routers, potentially creating many transient routing loops that can last for a long time. This limits the scalability of the routing protocols to large routing areas.

Mobile ad hoc network (MANET) is a collection of several wireless devices or mobile users that can communicate among themselves over wireless links in a peer to peer basis and thereby creating a dynamic, arbitrary graph. But some adverse characteristics of MANET like dynamic topology, limited bandwidth, link failure and energy constraints, imposes new demands on routing protocol. This paper aims to study the performance evaluation and comparison of three prominent routing protocols: Destination Sequence Distance Vector (DSDV), Ad-hoc On demand Distance Vector (AODV) and Optimized Link State Routing (OLSR), in a real life scenario. In a given scenario, students investigate the historical site in which number of packets being sends and number of nodes in the network affects the communication reliability. Extensive simulations are made to evaluate the performance of these protocols using various performance differential metrics like packet delivery ratio, total energy consumption and throughput using NS-3.29. In the end it is seen that in most simulation results, proactive routing protocols (DSDV, OLSR) performed significantly better than reactive routing protocols.

IP routing protocols, such as OSPF (open shortest path first) or BGP (border gateway protocol), have many configurable parameters (e.g., timers) and interact with each other in complex ways. Network operators may need to explore numerous candidate configuration changes before identifying a choice. In this paper, from the point of view of the economics of the Internet backbone, we propose a potential profit loss metric to evaluate configurations. Then we focus on analyzing the potential profit loss caused by link state changes under different configurations. We give quantitative relations between the potential profit loss and the major influential factors: OSPF timers, BGP timers and failure duration. From the quantitative relations we can see that appropriate configurations can reduce the profit loss much.

An unmanned aerial vehicle communication Networks (UAVCN) is a group of UAVs (unmanned aerial vehicles) that is able to communicate and trigger information to each other for a particular mission. This network node is power limited. However, the routing mechanism should be improved which extend the lifetime and performance of UAV nodes. This manuscript intends to introduce a concept of a cross-layer method for efficient power and routing for UAVCN to increase communication performance. The cross-layer methodology integrates the physical, link and network layer. An efficient power optimized link state routing (EP-OLSR) protocol is proposed which is an extension to optimized link state routing (OLSR) protocol. The proposed routing protocol evaluated by developing scenarios of UAVCN in OPNET modeler 14.5. The simulation is carried out by implementing OLSR and EP-OLSR using different network parameters and compared the routing protocols performance. The results showed that the EP-OLSR maximizes network performance efficiency as compared to OLSR. It minimizes the delay and maximizes the throughput and increases the network performance.

Streaming transmission on MANETs requires a high data delivery rate, few jitters and short delay, while consuming little network bandwidth. This paper presents the Neighbor-Aided Multicast Protocol for Streaming transmission on MANET (NAMPS). NAMPS is an on-demand, mesh-based protocol which provides multiple paths for data transmission. The key issue in mesh-based streaming transmission is the maintenance of the mesh structure. This involves the detection of the change to the mesh and restructuring of the mesh. In this paper, we take advantage of the continuous streaming packets and broadcast signals in wireless radio to detect the changes in link states. For the restructuring problem, we propose to use mesh neighbor to maintain group information, which facilitates route recovery and optimization. The simulation results show that NAMPS has both high effectiveness and efficiency.

In this paper, we propose an efficient routing algorithm based on AODV for the Mobile Hybrid Wireless Networks (MHWNs), which consists of the mobile ad hoc networks (MANETs) and an infrastructure wireless networks (such as cellular networks). In MANETs, the performance of the networks has been greatly challenged by the mobility from nodes and link state changes, while the link in cellular networks remains stable link with the mobile stations. This algorithm for routing construction takes advantage of the features of MHWNs, such as hybrid radio channels and nodes heterogeneity, to accomplish the bi-direction routing discovery on demand. Our results show that the performance of MHWNs is improved in the time and overhead for route path discovery process the under our bi-direction route algorithm.

Ad Hoc Routing with Distributed Ordered Sequences

A new routing protocol for ad hoc networks, called zone-based hierarchical link state routing, is proposed. In this protocol, the network is divided into non-overlapping zones. Each node only knows the node connectivity within its zone and the zone connectivity of the whole network. The link state routing is performed on two levels: local node and global zone levels. Unlike other hierarchical protocols, there is no cluster head in this protocol. The zone level topological information is distributed to all nodes. This peer-to-peer manner mitigates the traffic bottleneck, avoids single point of failure and simplifies mobility management. Since only zone ID and node ID of a destination are needed for routing, the route from a source to a destination is adaptable to changing topology. The zone ID of the destination is found by sending one location request to every zone. Simulation results show that our location search scheme generates less overhead than other schemes based on flooding. The results also confirm that the communication overhead for creating and maintaining the topology in our protocol is smaller than that in flat link state routing. This new routing protocol provides a flexible, efficient and effective approach to accommodate changing topology in wireless networks.

The purpose of this study is to select a robust and scalable routing protocol and to estimate the bandwidth overhead for extremely mobile, volatile and bandlimited tactical networks. The objective is to determine the suitability of such protocols for application to DARPA-sponsored SUO SAS (small unit operation situation awareness system) tactical networks. As it is well known, a critical issue for such networks is that routing control overheads increase rapidly with network size, thereby limiting their scalability. This paper presents a link-state proxy flooding protocol (LSPFP) with flat proxy architecture (FRA) which, as shown through analytical approximation of control overhead traffic, meets the scalability requirements of tactical networks. The generic routing concept is used to derive the analytical approximation equation, rather than a specific link state protocol.

An adhoc network is a collection of mobile nodes connected by a wireless link, where each node acts as a router. In order to facilitate the communication within the network, a routing protocol is needed. Due to bandwidth constraint and dynamic topology of the mobile adhoc Networks supporting Quality of Service (QoS) is challenging task. The aim of this work is to present QoS enabled routing protocol in adhoc networks and compare it with normal routing protocol. The Optimized Link State Routing (OLSR) protocol is an optimization of the classical link state protocol, which is used for implement the QoS. Such protocol is adopted for the reason that it reduces the size of control messages and minimizes the overhead from the flooding of control traffic. The performance of both routing and QoS routing protocols are evaluated using Network simulator Ns-2.QoS enabled routing protocol shows a significant improvement in protocol performance metrics applied in our measurements, such as packet delivery ratio, packet loss and delay.

An ad hoc network, a self-organizing wireless network is made up of mobile nodes, each node act as relay for providing data communication. The topology of the ad hoc networks changes often and needs large and frequent exchange of data among the network nodes for efficient routing. Existing routing protocols are distance vector method and link state routing protocols. The location information of the adhoc network nodes are broadcasted within the transmission range. The enemy can receive the location information of the nodes. Current position aided routing protocols were not designed for use in high risk environment. We have proposed a method for secured routing in adhoc network. It is a hierarchical method to solve the above problem. This method need not maintain the route information explicitly. This reduces the number of query control messages and suits well in dynamic environment. This method is better adaptive to dynamic environment than the present proactive, reactive and zone routing protocol methods (ZRP) and improves the security, efficiency and performance in ad-hoc routing.

Order of FIB updates seldom matters: Fast reroute and fast convergence with interface‐specific forwarding

In this paper we present a stepwise formal development of the Optimised Link State Routing (OLSR) protocol in Event-B. OLSR is a proactive routing protocol which finds routes for different destinations in advance by exchanging control messages through the network. As a consequence, whenever a data packet is injected into the network can be delivered to a certain destination immediately. To achieve this, routing tables in OLSR are continuously updated, by following a rather complicated algorithm. By modelling OLSR in Event-B, we address the scalability problem of our previous work [1], and structure the OLSR complexity in five distinct abstraction layers. These layers are manageable to understand and to verify and are linked to each other by refinement. As Event-B is supported by a theorem proving platform (Rodin), we model and prove functional properties of OLSR in an automated and interactive manner, at a highly general level. Our approach can serve as a proof-of-concept to be adapted to modelling and verifying of the other routing protocols for large-scale networks.

SUMMARYVirtual local area networks (VLANs) are widely used in many enterprises, campuses, and data‐centre networks. Although VLANs can restrict broadcast domains and contain hosts in one network or separate networks, the management of VLANs is an ad hoc and error‐prone work. In this paper, we design and implement a centralized and semi‐automatic system for VLAN management (CSS‐VM). Based on the physical network topology and user group (examples are engineering, student cluster, and faculty cluster) information, CSS‐VM can decide the number of VLANs that each user group would be partitioned into. In addition, CSS‐VM can not only monitor the status of devices and links but can also calculate an optimal spanning tree for each affected VLAN after a link or device failure is detected, so that it does not need to enable the Spanning Tree Protocol on devices but still has the ability of converging from device or link failures and avoiding bridging loops. We have evaluated CSS‐VM on the topology and VLAN partition data of an operational enterprise network. Our results show that CSS‐VM can obviously keep the broadcast traffic cost reasonable, efficiently partition and configure VLANs, quickly converge from link and device failures, and intelligently make a balanced use of links. Copyright © 2014 John Wiley & Sons, Ltd.

The first comparison of the performance of name-based content routing protocols based on distance vectors and link-states is presented. The protocols used for this comparison are the Named-data Link State Routing (NLSR) protocol, which is the main representative of name-based content routing based on link states, and the Distance-based Content Routing (DCR) protocol, which is the first name-based content routing protocol based on distance vectors. In the simulation of NLSR, the signaling of NLSR is simplified to minimize the overhead it incurs sending link state advertisements (LSAs), such that a single transmission is need to send an LSA, rather than multiple transmission as is the case with NLSR. The results of simulations show that the ideal version of NLSR requires fewer control messages to react to changes of name prefixes when the number of replicas is very small, and DCR incurs less signaling overhead to react to topology changes or changes in name prefixes when the number of replicas is large.