Jennifer S. Raj

Self-Organizing Hierarchical Structure for Wireless Networks

In this paper a novel self organizing structure is proposed to improve the performance of ad hoc networks in various traffic conditions. Self organization is used to avoid node failure and link failures for huge traffic conditions. A new methodology is proposed with four different traffic environments, topologies and the entire network follows the hierarchical architecture. In each case one node involved in routing named as backbone. The performance of this structure is compared with conventional dynamic source routing in network simulator (ns-2). In the simulation throughput, packet rate and delay performance of the network is analyzed.

A Localized Computing Approach for Connectivity Improvement Analysis in Wireless Personal Networks

A fundamental problem that confronts wireless networks are localization, mobility maintenance and number of neighbors required to maintain the connectivity. To overcome this problem and achieve a better quality of service, a self stability model is introduced, named as localized tree model which includes min and max routing methods. This work is based on node degree, neighbor’s information and coverage area. Based on the mobility requirements of the network, dynamic structures are formed with minimum control load and complexity. Main objective of the research is to obtain the network parameters from the connectivity analysis. The performance of the proposed approach is witnessed by analyzing the parameters like scalability, packet delivery ratio and connectivity efficiency.

Construction of virtual backbone to support mobility in MANET — A less overhead approach

Constructing a Virtual backbone (VB) has been widely used to reduce the communication overhead. Previous research works emphasize on constructing the virtual backbone and do not consider the local reconstruction of virtual backbone with less control overhead and balanced manner. In this paper, we propose a VB local reconstruction algorithm which is able to reconstruct the VB locally during the node movement. The Reconstruction of virtual backbone (R-VB) in MANET is achieved by exchange of tiny control packet between backbone nodes and non VB nodes. To handle the connectivity of the nodes computations depends on local to a large extent. Decisions of joining and leaving the backbone are made locally at nodes. Thus it is highly self-stabilized even under dynamic topologies. Our simulation results show that the proposed approach outperforms several existing approaches in terms of connectivity maintenance and less communication overhead. We present the performance of R-VB in terms of backbone size, delay and packet transmitted per each node. The performance of our algorithm is witnessed by simulation results.

Secured Self Organizing Network Architecture in Wireless Personal Networks

Secured self organizing network is an approach to computer network architecture that seeks to address the technical issues in heterogeneous networks that may lack continuous network connectivity. In delay tolerant network packets storage exists when there is any link breakage between the nodes in the network so delay is tolerable in this type of network during the data transmission. But this delay is not tolerable in wireless network for voice packet transmission. This evokes the use of wireless networks. In a network, different wireless network topologies are interoperating with each other so the communication across the network is called overlay network. This network is vulnerable to attacks due to mobile behaviour of nodes and frequent changes in topologies of the network. The attacks are wormhole attack and blackhole attack is analysed in this paper. They are critical threats to normal operation in wireless networks which results in the degradation of the network performance. The proposed recovery algorithm for wormhole and the isolation of blackhole will increase the performance of the network. The performance metrics such as throughput, packet delivery ratio, end–end delay and routing overhead of the network are evaluated.

A self-organized structure for mobility management in wireless networks

The objective of this work is to analyse performance of unstable mobile nodes with self-organization structures in Delay Tolerant Networks (DTN). This process enables the nodes to utilize their power fairly, and ensures that the links are established between nodes and used to improve the connectivity. In this paper two approaches are proposed: 1. Self-Healing (SH) and 2. Unstable Topology Structure (UTS) approaches based on localized computations. The proposed work is proven with simulations by analysing node degree, coverage area and Quality of Service (QoS) parameters. The performance of the work is analysed in a network simulator with mathematical models.

Secure interoperable architecture construction for overlay networks

Delay-tolerant networking (DTN) is an approach to computer network architecture that seeks to address the technical issues in heterogeneous networks that may lack continuous network connectivity. Examples of such networks are those operating in mobile or extreme terrestrial environments, or planned networks in space. In Disruption Tolerant Networks packets storage exists when there is any link breakage between the nodes in the network so delay is tolerable in this type of network during the data transmission. But this delay is not tolerable in wireless network for voice packet transmission. This evokes the use of wireless networks. Different wireless networks are interoperating with each other so the communication across the network is called overlay network. This network is vulnerable to attacks due to mobile behaviour of nodes. One of these is the wormhole attack. It is a critical threat to normal operation in wireless networks which results in the degradation of the network performance. It can be identified by using a technique called forbidden topology. The proposed recovery algorithm will increase the performance of the network. The performance metrics such as throughput, packet delivery ratio and delay are evaluated.

Ad hoc node connectivity improvement analysis - Why not through mesh clients?

A mobile ad-hoc network (MANET) is a complex distributed system with unpredictable node movements, which results in frequent node disconnectivity. In a MANET, each node works independently, using the resources based on individual need. The main problem with this arises during the movement of the nodes and random utilization of network resources. This work attempts to solve the mobility maintenance issues using three mesh structures; (i) mesh tree (MT), (ii) mesh backbone (MB) and (iii) mesh cluster (MC). The mobility maintenance architectures are formed based on a localized connectivity analysis and the node degree as a key parameter for network construction. The performance of the proposed work is analysed through mathematical models and simulation results.

Efficient topology control in wireless networks using minimum Backbone updates

The objective of the paper is to implement topology control by maintain minimum degree and connectivity between nodes from the Virtual-Backbone (VB) updates. VB construction is very familiar, to reduce flooding and broadcast storm problem in wireless networks. Nodes in MANET, move anywhere at any time, it requires strong topology and connectivity maintenance between VB and other nodes. To overcome this problem we provide the topology maintenance procedure and connectivity maintenance using 2-connected graph approximation. Stable topology is achieved by connection maintenance between virtual backbone nodes by providing minimum rerouting and connection balanced routing between nodes. We proposed a localized algorithm (Backbone based Topology Control Algorithm, BTCA) to support minimum degree nodes, by reducing the number of connections in one VB and maintain network topology. Our results are witnessed by simulation.