Most of the routing protocols in wireless ad hoc networks, such as DSR, assume nodes are trustworthy and cooperative. This assumption renders wireless ad hoc networks vulnerable to various types of Denial of Service (DoS) attacks. We present a distributed probing technique to detect and mitigate one type of DoS attacks, namely malicious packet dropping, in wireless ad hoc networks. A malicious ...

Denial-of-service (DoS) attacks on wireless sensor networks (WSNs) can deplete network resources and energy without much effort on the part of an adversary. Packetdropping attacks are one category of DoS attacks. Lightweight solutions to detect such attacks on WSNs are needed. Current techniques for detecting such attacks in ad hoc networks need to monitor every node in the network. Once they d...

We examine optimal Linear Quadratic Gaussian control for a system in which communication between the sensor (output of the plant) and the controller occurs across a packet-dropping link. We extend the familiar LQG separation principle to this problem that allows us to solve this problem using a standard LQR state-feedback design, along with an optimal algorithm for propagating and using the inf...

A network Quality of Service (QoS), characterized in that the specifying of various factors on the basis of packet delay Use and loss tolerance requirements. Unexpected natural application requesting the wireless channel Certain mechanisms to meet QoS requirements. Traditionally, Medium Access Control (MAC), and network layers to this Tasks. However, do not take these steps (fading) channel Con...

This paper presents two analytical models for TCP Reno and TCP Tahoe. For each model an algorithm is derived to calculate the utilizations and packet drop rates. The accuracy of the models is verified by comparing the calculated results versus simulation results. These results show that the TCP Reno is superior to Tahoe by having higher percentage of utilization and lower percentage of packet d...

This paper describes a programmable switch architecture that can be dynamically tuned to support flexible quality of service metrics for flows in the Internet. The switch architecture consists of six key components: scheduling, flow aggregation, queueing, packet-level admission control, packet dropping, and feedback. We show that it is possible to achieve a wide range of QoS behavior ranging fr...

The dynamic topology of Mobile ad hoc Network {MANET) allows nodes to join and leave the network at any point of time. This dynamic property of MANET has rendered it vulnerable to passive and active attacks by malicious nodes. In this paper we propose a new trust based relationship among the nodes to combat the packet dropping attack. In our scheme we considered the Dynamic Source Routing (DSR)...

a mobile ad hoc network (MANET) is a self-organizing, self-configuring confederation of wireless systems. MANET devices join and leave the network asynchronously at will, and there are no predefined clients or server. The dynamic topologies, mobile communications structure, decentralized control, and anonymity creates many challenges to the security of systems and network infrastructure in a MA...

Ad hoc networks are a new networking paradigm characterized by a dynamic topology and the absence of a predefined infrastructure. As a consequence, ad hoc networks are more vulnerable to attacks than traditional networks. The mechanisms used so far for protecting these networks are authentication and encryption. The latter, however, seem to be inefficient against malicious packet dropping and d...

In PCS networks, the multiple access problem is characterized by spatially dispersed mobile source terminals sharing a radio channel connected to a fixed base station. In this paper, we design and evaluate a reservation random access (RRA) scheme that multiplexes voice traffic at the talkspurt level to efficiently integrate voice and data traffic in outdoor microcellular environments. The schem...