1. Secure Group Communications in Wireless Sensor Networks December 8, 2003 CS 526 Advance Internet and Web Systems Patrick D. Cook

2. Agenda  Introduction  Security  Proposed Solutions  Conclusion  References

3. Introduction

4.  Ad hoc networks –Mobile Ad Hoc Networks (MANET) –Wireless Sensor Networks  Security –Confidentiality –Integrity –Availability

5. Security

6. Security - Resources  Maximum security with minimum resources –Computational Resources (i.e. CPU) –Memory –Communication Bandwidth –Limited Communication Range

7. Security - Threats  Disclosure –Passive Eavesdropping  Deception –Modification of messages  Disruption –Denial of Service Attacks  Usurpation –Spoofing/Masquerading

8. Security Combat- Cryptography  Symmetric Key –DES –Triple DES –AES (Rijandel)  Asymmetric Key –RSA  Key management

9. Proposed Solutions

10.  TinySec –University of California – Berkeley  Tiny Public Key (TinyPK) –BBN Technologies  Localized Encryption and Authentication Protocol (LEAP) –George Mason University

11. TinySec  The core of TinySec is an efficient block cipher and keying mechanism that is tightly coupled with the Berkeley TinyOS radio stack.  TinySec currently utilizes a single, symmetric key that is shared among a collection of sensor network nodes.

12. TinyPK  TinyPK stands for Tiny Public Key, also know as "Lightweight Security for Wireless Networks of Embedded Systems".  The goals of the project are to develop security services for wireless networks of low-power sensor devices.  The project has completed an implementation of RSA on the motes

13. LEAP  LEAP recognizes the unique routing capabilities of the motes and treat individual nodes separately.  It uses four types of keys for each sensor node – an individual key, a pair-wise key, a cluster key and a group key.  LEAP uses an efficient protocol for inner-node traffic and authentication.  The analysis of the 4 tuple key operation is about –[ 2(d – 1) 2 / (N – 1) + 2 ] in a network size of N and every node has a connection d. A large N will further reduce the cost.

14. Conclusion

15.  TinySec  LEAD  TinyPK

16. References  http://www.cs.berkeley.edu/~nks/tinysec/ http://www.cs.berkeley.edu/~nks/tinysec/  http://portal.acm.org/ http://portal.acm.org/  http://www.is.bbn.com/projects/lws-nest/ http://www.is.bbn.com/projects/lws-nest/  Computer Security: Art and Science Matt Bishop