A Study on Advancements on the Zone Routing Protocol of Hybrid Ad Hoc Networks

The Ad hoc networks are decentralized type of wireless network. The ad hoc networks incorporate several protocols that are used to mainly serve the process of communication from one node to another. The routing protocols are categorized as Reactive and Proactive Routing Protocols. To overcome the disadvantages of these both, the Hybrid Routing Protocol has been proposed. Zone Routing Protocol is one such Hybrid Ad Hoc Network. This paper mainly focuses on the enhancements made on the Zone Routing Protocol and evaluated against few parameters. Each enhancement is carefully studied and analyzed for their characteristics and compared to the Zone Routing Protocol

Upgraded Scalable Virtual Treebased Multicast Routing Protocol for Secured Packet forwarding in MANET's

ABSTRACT: Now a day's Mobile ad-hoc networks became a popular subject for research due to its wide utilization in different areas, and various studies have been made to increase the performance of ad hoc networks and support more advanced mobile computing and applications. Multicasting is a useful operation that facilitates group communications in MANETs. There are some problems of the existed mobile computing applications are multicast group membership management, zone construction and efficient forwarding of packets to all the group members over the dynamic network topology for a large group size or network size. This paper concentrated specifically, on efficient packet forwarding through a virtual-zone-based structure, and the location service for group members is integrated with the membership management. Both the control messages and data packets are forwarded along efficient tree-like paths, but there is no need to explicitly create and actively maintain a tree structure. The stateless virtual-tree-based structures significantly reduce the tree management overhead, support more efficient transmissions, and make the transmissions much more robust to dynamics. By upgrading the USVGM protocol with virtual-zone-based structure and tree-like paths we achieved higher performance and reliable and scalable data packet forwarding. Our simulation results demonstrate that Upgraded SVGM (USVGM) has high packet delivery ratio, low control overhead and multicast group joining delay under all test scenarios, and is scalable to both group size and network size. Keywords: USVGM, LAM, MZRP, LGT, LGS I. INTRODUCTION MANET is a collection of wireless nodes that can dynamically be set up any where and anytime without using any preexisting network infrastructure. It is an autonomous system in which mobile hosts connected by wireless links are free to move randomly and often act as routers at the same time. The traffic types in ad hoc networks are quite different from those in an infrastructure wireless network. Due to its popularity and wide advantages MANET are applied to different applications including battlefield communications, emergency relief scenarios, law enforcement, public meeting, virtual class room and other security-sensitive computing environments. Multicasting is a powerful scenario in MANET's environment. The design of the multicast scheme in MANET is more complex because of the dynamic change in the network topology and the limited bandwidth availability. Previous researches designed some ad hoc network routing protocols LAM [3], MZR

Hierarchical routing in MANETs using simple clustering

This thesis presents both a review of current MANET routing protocols and a new MANET routing algorithm. The routing protocols reviewed include representative samples from the three primary forms of routing found in MANETS: proactive routing, reactive routing and hybrid routing. Secure algorithms are given special treatment in the review. In addition several protocol enhancements are discussed. The proposed routing protocol is designed to support networks of a medium size, containing over 200 nodes but less than 3,000 nodes. The design is intentionally simple to allow ease of implementation in comparison with other MANET protocols that provide similar functionality

A caching scheme for routing in mobile ad hoc networks and its application to ZRP

A large class of routing protocols for MANETs, namely, reactive protocols, employ some form of caching to reduce the number of route discoveries. The simplest form of caching is based on associating a timeout with each cache entry. Such timer-based cache schemes can increase the protocol efficiency. However, if the timeout is not well-tuned, a severe performance degradation arises as entries are removed either too early or too late from the cache. In this paper, we address the problem of designing a proactive cache scheme that does not rely on any timer-based mechanism. This scheme guarantees that valid cached routes are never removed while stale routes are removed aggressively. This proactive cache scheme has been embedded in the Zone Routing Protocol (ZRP) framework and evaluated by an extensive simulation study

Architecture and performance of multi-hop wireless ad-hoc routing protocol (MultiWARP)

In recent years, a great deal of attention has been given to wireless connectivity solutions that are capable of establishing wireless ad-hoc networks between mobile nodes. Whilst most of these networks are formed using a combination of fixed and mobile infrastructure, completely infrastructure-less networks are thought to become more commonplace in the future. Moreover, this type of network structure seeks to utilise multi-hop connectivity between mobile nodes rather than the traditional single-hop connectivity established between fixed access points.The initial configuration phase and subsequent maintenance phase of a multi-hop wireless ad-hoc network requires the use of appropriate routing functions to exist between the mobile nodes. Therefore, it is essential that a routing protocol capable of determining correct and optimal routing path information in the presence of node mobility and the mobile radio environment be sought. Furthermore, it is beneficial to utilise the limited wireless bandwidth efficiently, such that a routing protocol should be designed specifically in the context of a multi-hop wireless ad-hoc network topology. This can be achieved through employing a non-hierarchical approach and using neighbouring nodes to act as intermediate relay nodes.The proposed routing protocol, called the Multi-hop Wireless Ad-hoc Routing Protocol (MultiWARP), is comprised of both a proactive and reactive routing component, thus forming a hybrid protocol which is able to exploit the benefits of each component. It is shown that manipulating these two components within the context of an awareness region, which divides the network into 2 regions, the routing overhead can be minimised. For the proactive component, the necessary network topology information that must be transmitted between neighbouring nodes is encoded within a routing update (RUPDT) packet. In this study, three alternative RUPDT encoding schemes have been formulated to encode the network topology in an efficient manner to reduce the RUPDT packet size.For the reactive component, a novel covercasting mechanism is designed that minimises the number of route request (RREQ) transmissions required to determine the routing path by utilising existing routing table information. Supplementary techniques are then utilised, such as snooping, route repair, and route optimisation to further optimise performance and minimise the route discovery delay (latency). This same covercasting mechanism is then utilised to efficiently transmit periodic RUPDT packets between neighbouring nodes to maintain routing table validity at each node, without having to resort to flooding which causes the “broadcast storm problem”. In addition, several route selection algorithms are considered which distribute traffic data between the intermediate relay nodes comprising the ad-hoc network.The performance and computational complexity of the proposed hybrid routing protocol is shown by means of computer simulations and theoretical analysis. Various traffic scenarios and topologies are presented to obtain the routing protocol performance metric results, and these are compared with other protocols found in the literature. For a multi-hop wireless ad-hoc network, it is shown that the proposed hybrid routing protocol, MultiWARP, is able to achieve higher average system performance in terms of improved throughput and stability performance when compared to other wireless ad-hoc routing protocols, such as DSR

An investigation of mobile ad-hoc network performance with cognitive attributes applied

Mobile Ad-Hoc Networks (MANETs) are known for their versatility, which is they are capable of supporting many applications. In addition to this versatility MANETs are quick to deploy without need for an existing predefined communications infrastructure. However, although the lack of infrastructure allows for the quick deployment of the data communications network, it adds many factors that hinder packet delivery. Such hindrances occur because of the dynamic topology caused by the mobility of the nodes which results in link breakages. Routing protocols exist that attempt to refresh available routes; however, this is after link breakages have occurred. The nodes also usually have constrained resources (i.e. energy source and limited bandwidth). This thesis presents a novel approach of network behaviour and management by implementing cognitive attributes into a MANET environment. This allows an application to better meet its mission objectives, decreases the end-to-end delay, and increases packet delivery ratio. The network is able to make observations, consider previous actions and consequences of the actions, and make changes based on the prior knowledge and experience. This work also shows how the network can better utilise limited resources such as bandwidth allocation by applying cognitive attributes. Simulations conducted show promising results and prove that an increase in network performance is possible if adopting a cross-layered approach and allow the network to manage and to ‘think’ for itself. Various simulations were run with various scenarios and results are presented without cognition applied, with partial cognition applied and with full cognition applied. A total of 52 simulations were run and from this the results were compared and contrasted. The analysis shows that cognitive attributes does increase network performance in the majority of applications