Fast Detection of Mobile Replica Node Attacks in Wireless Sensor Networks
Using Sequential Hypothesis Testing

[attachment=16310]

INTRODUCTION

ADVANCES in robotics have made it possible to develop a
variety of new architectures for autonomous wireless
networks of sensors. Mobile nodes, essentially small robots
with sensing, wireless communications, and movement
capabilities, are useful for tasks such as static sensor
deployment, adaptive sampling, network repair, and event
detection [4]. These advanced sensor network architectures
could be used for a variety of applications including
intruder detection, border monitoring, and military patrols.
In potentially hostile environments, the security of unattended
mobile nodes is extremely critical. The attacker
may be able to capture and compromise mobile nodes, and
then use them to inject fake data, disrupt network
operations, and eavesdrop on network communications.


2 PROBLEM DEFINITION
In this section, we first state the problem and the network
assumptions for our proposed scheme and then describe
the attacker models we use to evaluate our approach.


2.1 Problem Statement
We define a mobile replica node as a node having the
same ID and secret keying materials as a mobile node u. An
adversary creates replica node as follows: He first
compromises node u and extracts all secret keying materials
from it. Then, he prepares a new node u0, sets the ID of u0 to
the same as u, and loads u’s secret keying materials into u0.
There may be multiple replicas of u, e.g.,

there may be multiple compromised and replicated nodes.
Our goal is to detect the fact that both u and u0 (or u0

operate as separate entities with the same identity and keys.

2.2 Network Assumptions
We consider a two-dimensional mobile sensor network
where sensor nodes freely roam throughout the network.
We assume that every mobile sensor node’s movement is
physically limited by the system-configured maximum
speed, Vmax. We also assume that all direct communication
links between sensor nodes are bidirectional. This communication
model is common in the current generation of
sensor networks.