A Novel Structure with Dynamic Operation Mode for Symmetric-Key Block Ciphers

Modern Internet protocols support several modes of operation in encryption tasks for data confidentiality to keep up with varied environments and provide the various choices, such as multi-mode IPSec support. To begin with we will provide a brief background on the modes of operation for symmetric-key block ciphers. Different block cipher modes of operation have distinct characteristics. For example, the cipher block chaining (CBC) mode is suitable for operating environments that require self-synchronizing capabilities, and the output feedback (OFB) mode requires encryption modules only. When using symmetric-key block cipher algorithms such as the Advanced Encryption Standard (AES), users performing information encryption often encounter difficulties selecting a suitable mode of operation. This paper describes a structure for analyzing the block operation mode combination. This unified operation structure (UOS) combines existing common and popular block modes of operation. UOS does multi-mode of operation with most existing popular symmetric-key block ciphers and do not only consist of encryption mode such as electronic codebook (ECB) mode, cipher block chaining (CBC) mode, cipher feedback (CFB) mode and output feedback (OFB) mode, that provides confidentiality but also message authentication mode such as the cipher block chaining message authentication code (CBC-MAC) in cryptography. In Cloud Computing, information exchange frequently via the Internet and on-demand. This research provides an overview and information useful for approaching low-resource hardware implementation, which is proper to ubiquitous computing devices such as a sensor mote or an RFID tag. The use of the method is discussed and an example is given. This provides a common solution for multimode and this is very suitable for ubiquitous computing with several resources and environments. This study indicates a more effectively organized structure for symmetric-key block ciphers to improve their application scenarios. We can get that it is flexible in modern communication applications.