VEST Enhanced Smart Cards

VEST is a modern cipher that can be readily deployed to offer increased efficiency and/or improved functionality in smartcards. VEST can also be deployed to assist prevent real world problems such as identity theft and the emulation and cloning of cards. VEST efficiently implements the essential symmetric cryptographic functions in one low-area, highperformance multi-function module. VEST-4 reduces the cost of authentication applications by delivering the world's smallest published collision-resistant hash in silicon. This and other unique features of VEST can be exploited to deliver new standards of performance and protection in advanced smart card applications such as bus-level encryption, certified execution and hardware token validation during authentication. VEST may not suffer the huge overhead most other small area ciphers suffer to protect against side channel attacks. 1. The VEST Cipher Families VEST is a multi-purpose hardware-dedicated stream cipher targeted to efficient operation in semiconductor applications. There are four VEST family members, ranging from the 80-bit secure VEST-4 to the 256-bit secure VEST-32. VEST has a clean security record since its publication in 2005. All VEST family members belong to the most advanced cipher design class that delivers traditionally separate symmetric cryptographic functions in one module. VEST and Phelix [1] are both examples of a modern cipher that simultaneously combine the message encryption and authentication operations as an indivisible operation. In his paper [2], Professor Dan Bernstein uses Phelix as the ideal software reference to establish that combining encryption with authentication is a promising new research direction in increasing cipher design efficiency. While Phelix’s most advanced function offered encryption with embedded authentication, VEST takes multi-functionality much further, supporting (keyed and unkeyed) collision-resistant hashing critical for authentication applications in the one low area module. At approximately 5k ASIC gates, VEST-4 functionality includes the world's smallest published collision-resistant hash function. At approximately 10k ASIC gates, VEST-8 (256-bit key, 128-bit security claim) is both smaller and faster than the now defunct [3] Phelix cipher (256-bit key, 128-bit security claim) in ASIC when performing single pass authenticated encryption. VEST, has clear functionality and performance advantages over competing solutions.