Digital Commons Network^™

Route Recovery Schemes For Link And Node Failure And Link Congestion, Ibrahim Takouna

Theses

Link/Node failure occurs frequently causing service disruption in computer networks. Hardware techniques have been developed to protect the network from Link/Node failure. These techniques work in physical layer, therefore their convergence time is very small. On the other hand, many schemes have been proposed to mitigate the failure influence on the network. These schemes work in upper layers such as the network layer. However, hardware solutions faster than other schemes, but they are expensive. Link/Node failure causes all flows which were using the failed link/node are temporarily interrupted till a new path reestablished.

Three recovery algorithms have been proposed that …

Adaptive Turn-Prohibition Routing Algorithm For The Networks Of Workstations, Amey Bhaskar Shevtekar

Theses

Deadlock occurrence is a critical problem for any computer network. Various solutions have been proposed over last two decades to solve problem of deadlocks in networks using different routing schemes, like up/down routing algorithm used in Myrinet switches. However, most of existing approaches for deadlock-free routing either try to eliminate any possibility of deadlock occurrence, which can result in putting extra restrictions on the routing in the networks or put no restrictions on routing, which leads to other approach namely deadlock recovery. In this thesis emphasis is on developing hybrid approach for routing in wormhole networks, wherein some prohibition is …

Soft Fault Detection Using Mibs In Computer Networks, Sachin Arora

Theses

To improve network reliability and management in today's high-speed communication system, a statistical anomaly network intrusion detection system (NIDS) has been investigated, for network soft faults using the Management Information Base (Mm) traffic parameters provided by Simple Network Management Protocol (SNMP), for both wired and wireless networks. The work done would be a contribution to a system to be designed MIB Anomaly Intrusion Detection, a hierarchical multi-tier and multiobservation-window Anomaly Intrusion Detection system. The data was derived from many experiments that had been carried out in the test bed that monitored 27 MIB traffic parameters simultaneously, focusing on the soft …

Reduction Of False Positives In Fault Detection System Using A Low Pass Data Filter, Ranjit Salunkhe

Theses

Network traffic is bursty in nature and exhibits the property of self-similarity, the degree of which is measured by the Hurst parameter. Now, in any network there is always the possibility of the occurrence of fault traffic that can be caused due to faults or malfunction of a network component. Fault Detection Systems that check for traffic anomalies can trigger off an alert on the detection of any traffic behavior that deviates from normal. Such deviation is usually caused when a fault occurs. But in network traffic sudden bursts may occur due to the inherent behavior of a network application. …

Fair And Efficient Transmission Over Gbps Dual Ring Networks, Abdelnaser M. Adas

Theses

The advances in fiber optics technology provide large bandwidth and enable the support of a wide variety of services. New network architectures have been proposed, such as Metaring and Distributed Queue Dual Bus (DQDB), that try to take advantage of the new capabilities. Because of the very small packet transmission time relative to the feedback time a challenging issue in high speed networks is the efficient and fair share of the channel bandwidth among the competing users. In this thesis we first investigate and compare the performance of the Global and Local Fairness Mechanisms (GFM and LFM, respectively). They have …

Adaptive Map Configuration And Dynamic Routing To Optimize The Performance Of A Satellite Communication Network, Santhalingam Balasekar

Theses

Availability of alternate routes are shown to enhance the performance of non-hierarchical circuit switched networks at moderate load conditions on which the networks typically operate. But alternate routes introduce instability at heavy and overloaded conditions and at these load conditions the network performance is found to deteriorate. To alleviate this problem, one of the control mechanism used is to reserve a fraction of the capacity of each link for direct routed calls. In this work, the feasibility of changing the facilities of a satellite network is taken advantage in optimizing the performance of such a network. A mesh connected, circuit …

Interconnection Of X.25 Networks, Syed Ayaz Qutubuddin Ahmed

Theses

The purpose of this work was to investigate the performance of two interconnected X.25 networks via CCITT internet protocol X.75. Since internet protocol X.75 follow the same flow approach as X.25, we are allowed to model the acknowledgement queue in such a way that this queue provides a feed back path from destination to the source queue. Thus we are able to model our interconnected network as a closed queueing network with limited number of packets in transit within the network. Mean Value Analysis with Blocking (MVA) algorithm was applied to obtain the performance characteristics as the resources available were …

Configuring Maps For A Satellite Communication Network By Self- Organization, Yizhong Chen

Theses

There are several management tasks in a telecommunication network. Among which traffic management is one of the most important and difficult tasks. It is concerned with maximizing network efficiency when the network is under stress either due to overload or failure. New attempts to automate this task such as expert system based approach are yet to be perfected. In this thesis, we advocate a new concept of traffic management. Our scheme consists of two levels. At the first level, we introduce a Self-organization model to dynamically configure a map for a satellite communication network. The second level is a routing …

Fault Tolerant Benes Networks, Manoj Bhatnagar

Theses

A fairly large number of fault tolerant topologies have been proposed for the multistage interconnection networks in the recent years. However very few of these schemes have focused on the Benes network. This thesis presents two new fault tolerant architectures for the Benes network. The thesis includes algorithms to construct these fault tolerant networks from a Benes network and the reconfiguration procedure in the event of a fault. The hardware characteristics of both the fault tolerant networks have been analyzed and compared.