Hardware-software implementation of public-key cryptography for wireless sensor networks

As wireless sensor networks (WSNs) become more widespread, potential attacks against them also increase and applying cryptography becomes inevitable to make secure WSN nodes. WSN nodes typically contain only a constrained microcontroller, such as MSP430, Atmega, etc., and running public key cryptography on these constrained devices is considered a challenge. Since WSN nodes are spread around in the field, the distribution of the shared private key, which is used in a symmetric key cryptographic algorithm for securing communications, is a problem. Thus, it is necessary to use public key cryptography to effectively solve the key distribution problem. The RSA cryptosystem, which requires at least a 1024-bit key, is the most widely used public key cryptographic algorithm. However, its large key size is considered a drawback for resource constrained microcontrollers. On the other hand, RSA allows for extremely fast digital signature generation which may make it desirable in applications where messages transmitted by sensor nodes need to be authenticated. Furthermore, for compatibility with an existing communication infrastructure, it may be desirable to adopt RSA in a WSN setting. With this work, we show that, in spite of its long key size, RSA is applicable for wireless sensor networks when optimized arithmetic, low-level coding and some acceleration algorithms are used. We pick three versions of the MSP430 microcontroller, which is used widely on wireless sensor network nodes, and implement 1024-bit RSA on them. Our implementation achieves 1024-bit RSA encryption and decryption operations on MSP430 in only 0 . 047 s and 1 . 14 s, respectively. In order to achieve these timings, we utilize several acceleration techniques, such as the subtractive Karatsuba-Ofman, Montgomery multiplication, operand scanning, Chinese remainder theorem and sliding window method. To the best of our knowledge, our timings for 1024-bit RSA encryption and decryption operations are the fastest reported timings in the literature for the MSP430 microcontroller.

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Multi-Node of Synergy Certificateless Authentication in WSNs

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.263-266.3047 ◽

2012 ◽

Vol 263-266 ◽

pp. 3047-3051

Author(s):

Guang Cong Liu ◽

Yuan Jie Shi ◽

Cong Li

Keyword(s):

Wireless Sensor Networks ◽

Sensor Networks ◽

High Efficiency ◽

Low Cost ◽

Public Key Cryptography ◽

Security Requirements ◽

Public Key ◽

Wireless Sensor ◽

Certificateless Public Key Cryptography ◽

Certificateless Authentication

Certificateless Public Key Cryptography (CL-PKC) overcomes not only the key escrow problem in public key cryptography but also the cost of the certificate publishing and management in the Certificateless Public Key Cryptography (CL-PKC). No certificate public key cryptosystem just meet the requirements of this, but it relies on a special authentication server, which has high operating costs and lack of flexibility and it cannot meet the requirements of wireless sensor networks directly. Considering these problems, a multi-node of synergy certificateless authentication approach is proposed for WSN. The certificate of the nodes would be done by the certification set. And the set was consited of trusted neighbor nodes. Analysis indicates that this certification meets the security requirements of general wireless sensor networks and has advantages of low-cost and high efficiency.

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Advances in Security and Privacy in Wireless Sensor Networks

Cyber Crime ◽

10.4018/978-1-61350-323-2.ch802 ◽

2013 ◽

pp. 1654-1681

Author(s):

Dulal C. Kar ◽

Hung L. Ngo ◽

Clifton J. Mulkey ◽

Geetha Sanapala

Keyword(s):

Wireless Sensor Networks ◽

Sensor Networks ◽

Sensor Network ◽

Public Key Cryptography ◽

Sensor Nodes ◽

Public Key ◽

Wireless Sensor ◽

Identity Based ◽

Symmetric Key ◽

Symmetric Key Cryptography

It is challenging to secure a wireless sensor network (WSN) because its inexpensive, tiny sensor nodes do not have the necessary processing capability, memory capacity, and battery life to take advantage of the existing security solutions for traditional networks. Existing security solutions for wireless sensor networks are mostly based on symmetric key cryptography with the assumption that sensor nodes are embedded with secret, temporary startup keys before deployment thus avoiding any use of computationally demanding public key algorithms altogether. However, symmetric key cryptography alone cannot satisfactorily provide all security needs for wireless sensor networks. It is still problematic to replenish an operational wireless sensor network with new sensor nodes securely. Current research on public key cryptography for WSNs shows some promising results, particularly in the use of elliptic curve cryptography and identity based encryption for WSNs. Although security is essential for WSNs, it can complicate some crucial operations of a WSN like data aggregation or in-network data processing that can be affected by a particular security protocol. Accordingly, in this chapter, the authors summarize, discuss, and evaluate recent symmetric key based results reported in literature on sensor network security protocols such as for key establishment, random key pre-distribution, data confidentiality, data integrity, and broadcast authentication as well as expose limitations and issues related to those solutions for WSNs. The authors also present significant advancement in public key cryptography for WSNs with promising results from elliptic curve cryptography and identity based encryption as well as their limitations for WSNs. In addition,they also discuss recently identified threats and their corresponding countermeasures in WSNs.

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