Chapter 4 - Securing large datasets involving fast-performing key bunch matrix block cipher

Abstract

The steep rise in the variety and volume of data is promoting new data storage techniques, in almost all sectors. In addition, the seamless connectivity of networks spread across multiple platforms and locations has added a new dimension in the secure storage and access of information. Governments and laws also stress the secrecy and privacy of data stored at their behest and prevention of its misuse. For this, numerous block ciphers are used. One of the prominent features in the development of any cipher is the number of bits in the keys chosen. The larger the length of key, the higher the security it offers. However, increasing the number of bits in the key chosen would result in an exponential increase in the response time required for executing cryptographic procedures in legacy systems. Most of the available block ciphers are impractically time-consuming, with longer keys, and raise serious concerns when highly confidential data in huge volumes are to be transferred across computer networks, with improved security. Addressing this issue, to provide security and privacy for large datasets at rest as well as during transmission, a novel algorithm is developed which uses a large key that offers higher security against attacks on data confidentiality with lower computational costs than the conventional ones. In this chapter, as an illustration, a large key bunch matrix is chosen with 2048 bits and the block cipher is developed, although the size of the key is further expandable with very trivial changes in the computational costs that would be incurred, in spite of using a lower configured computing system. The relaxation of the key-size constraint is realized, thus paving the way for using the keys with a large number of bits in the cryptosystem and enhancing security, without overburdening the system with complex and time-consuming computations involved in the encryption and decryption procedures.