Implementation and Benchmarking of Hardware Accelerators for Ciphering in LTE Terminals

Sebastian Hessel, David Szczesny, Nils Lohmann, Attila Bilgic, Josef Hausner

52nd IEEE Global Communications Conference (GLOBECOM 2009), pp. 1-7, Honolulu, Hawaii, USA, Nov. 30 - Dec. 4 2009.


In this paper we investigate hardware implementations of ciphering algorithms, SNOW 3G and the Advanced Encryption Standard (AES), for the acceleration of the protocol stack layer 2 in the 3G Long Term Evolution (LTE). This analysis is based on timing requirements from execution time measurements in a simulated mobile phone platform, where we apply data rates of 100 Mbit/s and above (200 and 300 Mbit/s) to account for LTE and beyond LTE investigations. Different architectures for both algorithms are explored in order to meet the performance requirements, while keeping the power and area budget at a reasonable level. Therefore, a hardware analysis is done using a standard cell library of Faraday^Òs 90nm CMOS technology. Finally, the cryptographic substitution box with one-hot encoding emerges as the best solution for both ciphering schemes. Additionally, the 128-bit data path in the AES is identified as the most suitable architecture for LTE terminals, whereas a dual-AES approach turns out to be a candidate for data rates far beyond LTE (like LTE-Advanced).