Wireless Sensor Networks Security

1
Wireless Sensor Networks Security

• Lindsey McGrath and Christine Weiss

2
Agenda

• Introduction
• Background - Problem Statement
• Requirements for Sensor Network Security
• Attacks on Sensor Networks
• Security Services
• Challenges
• Conclusion

3
Introduction

• What is a Sensor Network ?
• A heterogeneous system combining tiny sensors and
  actuators with general-purpose computing
  elements. Most consisting of hundreds or
  thousands of low-power, low-cost nodes deployed
  to monitor and affect the environment.
• What are they used for?
• Ocean and wildlife monitoring.
• Monitoring of manufactured machinery.
• Building safety.
• Earthquake monitoring.
• Variety of military applications.
• Medical monitoring and research.
• Addressing Sensor Network Securityexisting
  security mechanisms are inadequate! What are the
  security issues? What security services will
  work?

4
Background-Problem Statement

• Network Assumptions
• Insecure links non denial of eavesdropping.
• Replay and injection of packets.
• Non tamper resistant.
• Trust Requirements
• Base station and aggregation point
  trustworthiness.
• Threat Models
• Outsider vs. insider attacks.
• Mote-class vs. laptop-class attackers.
• Security Goals
• Integrity, authentication, freshness and
  confidentiality.

5
Requirements for WSN Security

• Data Confidentiality omission of data leaks to
  neighboring networks.
• Data Authentication verification of
  sender/receiver.
• Data Integrity non altered transmission of
  data.
• Data Freshness ensuring data is recent while
  allowing for delay estimation.

6
Attacks on WSN

• Spoofed, altered and replayed routing information
• Selective Forwarding
• Sinkhole attacks
• The Sybil attack
• Wormholes

7
Security Services

• Link-layer encryption and authentication
• Multi-path routing
• Identity verification
• Bidirectional link verification
• Authenticated broadcasts

8
Challenges

• The existing infrastructure is already
  resource-starved.
• Communication bandwidth
• Power
• Computational power
• Preventing insider attacks.
• Sinkhole attacks and wormholes no known
  countermeasures to apply after the protocol is
  designed.
• Building multi-hop routing topology - Nodes
  within one or two hops of the base station are
  attractive to intruders.

9
Conclusion

• Currently proposed routing protocols for WSNs are
  insecure but vital.
• Link layer encryption and authentication
  mechanisms provide reasonable defense for
  mote-class outsider attacks.
• Cryptography is inefficient in preventing against
  laptop-class and insider attacks.
• Remains an open problem for additional research
  and development.

10
Resources

• Perrig, A., Stankovic, J., and Wagner, D. 2004.
  Security in wireless sensor networks. Commun. ACM
  47, 6 (Jun. 2004), 53-57.
• Perrig, A., Szewczyk, R., Tygar, J. D., Wen, V.,
  and Culler, D. E. 2002. SPINS security protocols
  for sensor networks. Wirel. Netw. 8, 5 (Sep.
  2002), 521-534.
• Karlof, C. and Wagner, D. Secure routing in
  wireless sensor networks Attacks and
  countermeasures. In Proceedings of the 1st IEEE
  International Workshop on Sensor Network
  Protocols and Applications (Anchorage, AK, May
  11, 2003).
• Hu, Y.-C., Perrig, A., and Johnson, D. Packet
  leashes A defense against wormhole attacks in
  wireless ad hoc networks. In Proceedings of IEEE
  Infocom 2003 (San Francisco, Apr. 1--3, 2003).
• L. Zhou and Z. Haas, Securing ad hoc networks,
  IEEE Network Magazine, vol. 13, no. 6,
  November/December 1999.
• Y.-C. Hu, A. Perrig, and D. B. Johnson, Wormhole
  detection in wireless ad hoc networks,
  Department of Computer Science, Rice University,
  Tech. Rep. TR01-384, June 2002.