High-performance and energy-efficient sliced AES multi-block encryption for LTE mobile devices

Abstract

In this paper we present an efficient software im plementation of the Advanced Encryption Standard (AES) used in the confidentiality algorithm of the Long Term Evolution (LTE) protocol. Our implementation is based on slicing and merging the bytes of several data blocks to exploit processor's architecture width for multi-block encryption. In addition, an appropriate lookup table and data organization in memory are applied, combined with media processing instructions in order to enhance the performance of AES in embedded environments.Other optimized software implementations from literature are also explored and evaluated in comparison to the proposed implementation with respect to processing throughput and energy consumption using a multi-core based mobile phone platform.Simulation results show that the proposed implementation is the fastest among other implementations and achieves improvements in performance up to 69 % while providing S9 % of energy savings. Moreover, the presented implementation is scalable for multi-core execution. When running on two cores, it fulfills the LTE data rate of 100 Mbitls and extends energy savings to 68%, leading to a total of 13 times improvement in energy efficiency. I. I NTRODUCTIONThe speed of data transfer in mobile networks is continu ously increasing, reaching up to 100 Mbitls in the upcoming Long Term Evolution (LTE) standard. Security in cellular communication systems is based on cryptographic algorithms to encrypt and decrypt user data. These algorithms are com putationally expensive and require relatively long execution times. A former performance analysis of the LTE protocol stack in [1] identified ciphering as a time critical function. Thus providing an efficient ciphering implementation has a great impact on overall system performance. The energy consumption of software plays also a vital role in mobile devices due to its limited battery capacity.Ciphering algorithms in mobile handsets are typically ac celerated by dedicated hardware. Software implementations, however, enable sharing of computing resources between ci phering and other communication functionalities. In addition, it provides flexibility needed to support multiple cellular stan dards using different ciphering schemes. However, software implementations are relatively slow and therefore have to be efficient enough in order to fulfill the required timing constraints while consuming lowest energy possible. In this paper we introduce a novel software implementation of the confidentiality algorithm used in the LTE standard. The pro posed implementation exploits the processor architecture width to perform several ciphering operations simultaneously. As 978-1-61284-486-2/111$26.00 ©2011 IEEE embedded multi-core processors are expected to be deployed in future mobile devices [2], we also investigate how further speedups can be obtained by using multi-core processing. Fi nally, our implementation is evaluated against other optimized implementations from literature with respect to processing throughput and energy c...

LTE Security potential vulnerability and algorithm enhancements

“…The paper states the use of a multi-core based mobile phone platform, and the performance improvement is done with the help of simulations. [4] Their study infers an energy savings by 68%, an improvement of 13 folds. They also mention that flexibility is an important aspect to be considered and an optimized implementation called SAME is introduced which is capable of performing computation of AES based on byte slicing in order to cipher several data blocks simultaneously.…”

AES and SNOW 3G are Feasible Choices for a 5G Phone from Energy Perspective

“…From Table 1, we find the implementations in [9,10,11] are potential candidates for using in 5G since they meet the required throughput of 5G and Table 1. AES Implementations present their energy requirements which enable us to make a meaningful analysis.…”

“…AES Implementations present their energy requirements which enable us to make a meaningful analysis. In [10], the authors present an implementation called SAME that achieves 114 Mbps throughput using 2 cores of the processor of a mobile phone. The implementation is based on slicing and merging the bytes of several data blocks to exploit processor's architecture width for multi-block encryption.…”

Energy-Efficient Hardware Architectures for the Packet Data Convergence Protocol in LTE-Advanced Mobile Terminals

“…To our best knowledge, no research work has ever introduced hardware power reduction techniques for AES especially targeting its mode of operation in the LTE protocol. However, there are some attempts to accelerate both 128-EEA1 and 128-EEA2 algorithms by parallelizing them on an embedded ARM multicore processor [25,26]. e focus in these works was �rst to deliver an efficient implementation with the minimum possible instruction count.…”

“…Parallelism was then investigated and deployed at both algorithmic level (128-EEA1) and block level (128-EEA2) for further optimization of the processing time. In [25], different message blocks are dispatched to available cores for parallel processing. Energy savings were also achieved compared to single core implementations by exploiting the excess in performance gain for frequency and voltage scaling [9], or by mapping protocol stack soware to several small/big cores associated with different speeds and supply voltages [27].…”