Survey and Benchmark of Block Ciphers for Wireless Sensor Networks

Cryptographic algorithms play an important role in the security architecture of wireless sensor networks (WSNs). Choosing the most storage- and energy-efficient block cipher is essential, due to the facts that these networks are meant to operate without human intervention for a long period of time with little energy supply, and that available storage is scarce on these sensor nodes. However, to our knowledge, no systematic work has been done in this area so far.We construct an evaluation framework in which we first identify the candidates of block ciphers suitable for WSNs, based on existing literature and authoritative recommendations. For evaluating and assessing these candidates, we not only consider the security properties but also the storage- and energy-efficiency of the candidates. Finally, based on the evaluation results, we select the most suitable ciphers for WSNs, namely Skipjack, MISTY1, and Rijndael, depending on the combination of available memory and required security (energy efficiency being implicit). In terms of operation mode, we recommend Output Feedback Mode for pairwise links but Cipher Block Chaining for group communications

AES-CBC Software Execution Optimization

With the proliferation of high-speed wireless networking, the necessity for efficient, robust and secure encryption modes is ever increasing. But, cryptography is primarily a computationally intensive process. This paper investigates the performance and efficiency of IEEE 802.11i approved Advanced Encryption Standard (AES)-Rijndael ciphering/deciphering software in Cipher Block Chaining (CBC) mode. Simulations are used to analyse the speed, resource consumption and robustness of AES-CBC to investigate its viability for image encryption usage on common low power devices. The detailed results presented in this paper provide a basis for performance estimation of AES cryptosystems implemented on wireless devices. The use of optimized AES-CBC software implementation gives a superior encryption speed performance by 12 - 30%, but at the cost of twice more memory for code size.Comment: 8 pages, IEEE 200

The Melbourne Shuffle: Improving Oblivious Storage in the Cloud

We present a simple, efficient, and secure data-oblivious randomized shuffle algorithm. This is the first secure data-oblivious shuffle that is not based on sorting. Our method can be used to improve previous oblivious storage solutions for network-based outsourcing of data

KLEIN: A New Family of Lightweight Block Ciphers

Resource-efficient cryptographic primitives become fundamental for realizing both security and efficiency in embedded systems like RFID tags and sensor nodes. Among those primitives, lightweight block cipher plays a major role as a building block for security protocols. In this paper, we describe a new family of lightweight block ciphers named KLEIN, which is designed for resource-constrained devices such as wireless sensors and RFID tags. Compared to the related proposals, KLEIN has advantage in the software performance on legacy sensor platforms, while in the same time its hardware implementation can also be compact

Secure Communication using Identity Based Encryption

Secured communication has been widely deployed to guarantee confidentiality and\ud integrity of connections over untrusted networks, e.g., the Internet. Although\ud secure connections are designed to prevent attacks on the connection, they hide\ud attacks inside the channel from being analyzed by Intrusion Detection Systems\ud (IDS). Furthermore, secure connections require a certain key exchange at the\ud initialization phase, which is prone to Man-In-The-Middle (MITM) attacks. In this paper, we present a new method to secure connection which enables Intrusion Detection and overcomes the problem of MITM attacks. We propose to apply Identity Based Encryption (IBE) to secure a communication channel. The key escrow property of IBE is used to recover the decryption key, decrypt network traffic on the fly, and scan for malicious content. As the public key can be generated based on the identity of the connected server and its exchange is not necessary, MITM attacks are not easy to be carried out any more. A prototype of a modified TLS scheme is implemented and proved with a simple client-server application. Based on this prototype, a new IDS sensor is developed to be capable of identifying IBE encrypted secure traffic on the fly. A deployment architecture of the IBE sensor in a company network is proposed. Finally, we show the applicability by a practical experiment and some preliminary performance measurements