Motivation

1
Group-based Peer Authentication for Wireless
Sensor Networks
Taojun Wu, Nathan Skirvin, Jan Werner, Brano
Kusy, Akos Ledeczi, Yuan Xue (Vanderbilt
University)
Motivation
Simple Example
Analysis

• Each key represents a group, a node is in k
  groups if it contains k keys. When k is equal for
  all nodes, it needs to satisfy at least
• Unlike existing research, we focus at providing
  authentication. Hence our scheme does not require
  equal sized key rings, nor equal sized
  overlapping groups.

• Scenario Dirty Bomb Detection and Localization
• 1. Critical mission 2. Real-time 3. Constrained
  resources

Key Pre-distribution
Sensor A pretends to be C, appends message
authentication code (generated with key 1 4) to
outgoing messages

• Sensors have pre-distributed subset of keys, out
  of key pool
• Node-to-key mapping is publicly available to all
  sensors
• For the localization scenario, each mote has 4
  keys, reducing from 12, if pair-wise secret keys
  are used.

Measurement Results

• App. 2800 B in ROM, 200 B in RAM, including
  program assigned keys
• Computation time 5.3 ms
• Verification time lt 0.1 ms, 1.31.4 ms or 2.5
  ms, if receiver has 0, 1 or 2 keys in common with
  sender.

Objectives

• Meet flexible authentication demands
• Care only overall decision
• Allow uncertainty between few pairs
• Enable differentiated influence according to
  role
• Level security assurance among sensors
• Provide efficient and effective authentication
• Low computation requirement
• Less memory space usage

System Implementation

• We implement a component (MultiMAC) under TinyOS
  (based on SkipJack in TinySec)
• MultiMAC is part of the Dirty Bomb Detection and
  Localization demonstration (Vanderbilt and ORNL)
  of IPSN 2006. http//www.isis.vanderbilt.edu/proje
  cts/rips/

Acknowledgement
This is a collaborative work between Institute
for Software Integrated Systems and OAK Ridge
National Laboratory.