Cryptographic Operation Load-Balancing between Cryptographic Module and CPU

Mobile devices such as smartphones and tables have permeated into our daily lives and are now often indispensable because of the constant Internet access they provide. Furthermore, with ever increasing concerns regarding privacy and security, it has become popular to utilize cryptographic operations when accessing Web application servers from such devices. However, since such operations cause high loading on the central processing units (CPUs) of personal computers (PCs) or servers, mobile device CPUs now often come equipped with hardware cryptographic modules. These cryptographic modules are frequently utilized by many mobile device applications via a process known as offloading. However, when all cryptographic operations can be offloaded to cryptographic modules, device CPUs may become idle, which is an ineffective use of total computing resources. In this paper, we propose the simultaneous balanced offloading of cryptographic operations to the cryptographic module of an AM3358 processor and CPU via load-balancing and then evaluate the performance of our implementation. We evaluated our proposed system and concluded that while it is capable of working effectively, in most cases files smaller than approximately 1000 bytes can be executed faster via the CPU alone, whereas when files are larger than 1000 bytes, the proposed system is faster. In the case of encrypting or decrypting a 7 Kbyte file, our proposed system is twice as fast as ´CPU only´ operation.