Wenjia Li: Coping with Node Misbehaviors in MANETs, 4pm Tue 1/6/08, 325b ITE, UMBC

January 4th, 2009

Wenjia Li will present his dissertation proposal on ‘A Security Framework to Cope with Node Misbehaviors in Mobile Ad Hoc Networks’ which will be done under the supervision of Professor Anupam Joshi. The presentation will be at 4:00pm Tuesday, January 6, in ITE 325b. Here’s the abstract.

A Mobile Ad-hoc NETwork (MANET), as its name suggests, has no fixed infrastructure, and is generally composed of a dynamic set of cooperative peers, which are willing to share their wireless transmission power with other peers so that indirect communication can be possible between nodes that are not in the radio range of each other . The nature of MANETs, such as node mobility, unreliable transmission medium and restricted battery power, makes them extremely vulnerable to a variety of node misbehaviors. Wireless links, for instance, are generally prone to both passive eavesdropping and active intrusion. Another security concern in ad hoc networks is caused by the cooperative nature of the nodes. Attacks from external adversaries may disturb communications, but the external intruder generally cannot directly participate in the cooperative activities among the nodes, such as routing, because they do not possess the proper secure credentials, such as shared keys. However, compromised nodes, which are taken over by an adversary, are capable of presenting the proper secure credentials, and consequently can interfere with almost all of the network operations, such as route discovery, key management and distribution, and packet forwarding. Hence, it is essential to cope with node misbehaviors so as to secure mobile ad hoc networks.

In this dissertation, we address the question of how to ensure that a MANET will properly operate despite the presence of various node misbehaviors. We propose to build a framework that can cope with various node misbehaviors in a wise and adaptive manner. The main purpose of our proposed framework is to provide a platform so that the components that identify and respond to misbehaviors can better cooperate with each other and quickly adapt to the changes of network context. Therefore, policies are planned to be utilized in our framework in order to make those components correctly function in different network contexts. Besides the policy component, there are three other components, which fulfill the tasks of misbehavior detection, trust and reputation management, and route management, respectively. To validate and evaluate our proposed framework, we plan to implement our framework based on simulator.

In particular, the contributions of this dissertation are (i) Develop a framework to combine the functionalities of surveillance and detection of misbehavior, trust and reputation management, route management, and policy management so as to provide a high-level solution to cope with various misbehaviors in MANETs in an intelligent and adaptive manner (ii) Propose and implement a misbehavior detector based on the gossip-based outlier detection method, which relies on neither any pre-defined threshold nor any training data (iii) Take into account both first-hand information (direct observation) and second-hand information (indirect observation) during both misbehavior detection and trust management processes, in which first-hand information and second-hand information are merged by some intelligent methods (iv) Specify and enforce policies in the proposed framework, which makes the framework promptly adapt to the rapidly changing network context.

Gossip-Based Outlier Detection for Mobile Ad Hoc Networks

May 5th, 2008

In this week’s UMBC ebiquity meeting (10am Tue may 6 in ITE 325), PhD student Wenjia Li will talk about his research on security and MANETs. Guests are always welcome — just drop in. Here’s the title and abstract.

Gossip-Based Outlier Detection for Mobile Ad Hoc Networks
Wenjia Li, University of Maryland, Baltimore County

It is well understood that Mobile Ad Hoc Networks (MANETs) are extremely susceptible to a variety of attacks. Many security schemes have been proposed that depend on identifying nodes that are exhibiting malicious behavior such as packet dropping, packet modification, and packet misrouting. We argue that in general, this problem can be viewed as an instance of detecting nodes whose behavior is an outlier when compared to others. In this work, we propose a gossip-based outlier detection algorithm for MANETs. The algorithm leads to a common outlier view amongst distributed nodes with a limited communication overhead. Simulation results demonstrate that the proposed algorithm is efficient and accurate.