A Test-bed for Secure Hierarchical Data Aggregation in Wireless Sensor Networks

1. A Test-bed for Secure Hierarchical Data Aggregation in Wireless Sensor Networks Students: Vimal Kumar, Joshua McCarville-Schueths (Computer Science Department ) Faculty Advisor: Dr. Sanjay Madria, Computer Science Department • The Platform usedwas nesC on Tinyos 1.1.15 • Code was implemented on Mica2and TelosB motes. • Used TinyECC library for Elliptic curves with160 bit curve secp160r1. This provides160-bit encryption keys. • Data is encrypted by Elliptic curve ELGamal (ECEG) and signed by our modified version of Elliptic curve digital signature algorithm (ECDSA). • ECEG is a homomorphic encryption scheme and the modified ECDSA is an aggregate digital signature scheme. • Wireless sensors are small battery powered devices with wide applications in areas such as battlefield surveillance, wildlife monitoring, healthcare, etc. • The challenge on wireless sensors is to devise algorithms which require least energy so as to make the sensors last longer. • Since the biggest reason of power consumption on sensors is wireless communication, we focus on minimizing it. • Security operations are power intensive. In a secure protocol, such operations should be kept to a minimum while maintaining optimum security. INTRODUCTION IMPLEMENTATION 1 2 Traditional Encryption Enc[Message1] + Enc[Message2] ≠Enc[Message1 + Message2] Homomorphic Encryption Enc[Message1] + Enc[Message2] = Enc[Message1 + Message2] Digital Signatures Sign[Message1] + Sign[Message2] ≠ Sign[Message1 + Message2] Additive Digital Signatures Sign[Message1] + Sign[Message2] = Sign[Message1 + Message2] Base Station • DATA AGGREGATION • Intermediate nodes aggregate data • Data aggregation helps conserving energy by reducing the number of messages sent with in the network. I see 6 soldiers Base Station 3 SUM-Enc(101) SUM-Sign(101) SUM-PK(21,17) Children transmit the encrypted data , signature, and the public key to the parent Keeping soldier count using data aggregation Enc( 58) Sign(58) PK(21,19) Enc( 19) Sign(19) PK(11,10) Enc( 24) Sign(24) PK(13,11) • The results obtained by the implementation of the code on Mica2 motes are summarized in the table above. • The scheme replaces the decrypt, verify, encrypt and sign operations on the intermediate nodes, with the three operations , namely the addition of ciphertext, signatures and the public keys. • Energy Saving at Aggregators • MICA2 - 97.74 mJ • TELOSB - 100.39 mJ • The code for TELOSB is in the process of optimization. Its execution times and energy consumption can be further reduced. • Extend the network lifetime by further optimizing the code. • Minimize the redundancy of the messages in the network by implementing data compression at the source nodes. • Implementation of the algorithm on GumStix • This research is partly supported by Intelligent Systems Center. RESULTS FUTURE WORK • Develop a secure end to end data aggregation scheme with lesser power consumption. • Propose security operations(encryption, digital signatures) to support the end to end communication. • Write an efficient implementation of these security operations. • Write a reconfigurable implementation which can be easily customized to fit various platforms and motes. OBJECTIVES ACKNOWLEDGEMENTS REFERENCES Vimal Kumar, Joshua McCarville-Schueths and Sanjay Madria, “A Test-bed for Secure Hierarchical Aggregation in Wireless Sensor Networks, Demo paper in MASS 2010