Today the quick development of computers and networks not only enriches our everyday life, but also provides us with a convenient living environment. However, hackers are everywhere in the world. Hence, our sensitive data need to be securely protected. Currently, AES and DES as the most widely used block ciphering mechanisms are popularly employed to encrypt important data. But DES was publicly cracked several years ago. On the other hand, due to the fast computer processing speed and processing power, currently no one dare to say that AES is still secure. It may be cracked someday. Therefore, in this paper, we propose a secure encryption method, called the Random Wrapping Encryption Method (RWEM for short), which is developed by employing information of current time as a part of the parameters to wrap up ciphertext in its encryption process. If a file is encrypted at different time points, the content and the length of the wrapped ciphertext file will not be the same. Thus, it is hard for hackers to analyze and crack the ciphertext. We also analyze the security of the DES, AES and RWEM, and explain why the RWEM can effectively protect some specific attacks, and why it is more secure than the DES and AES.

An efficient fault restoration framework is proposed for accomplishing loopback recovery in optical networks. The pro posed p-cycle-based framework achieves both a minimal spare capacity requirement and a rapid restoration time. In the proposed approach, an algorithm designated as Star-Block is used to simplify the original topology to a 2-connected graph and to partition the graph into multiple blocks, where each block contains a center node and the minimum number of neighboring nodes that collectively form a complete cycle. The simplified graph is then restored to the original topology using conventional graph rules. The Block Selection algorithm is then used to assign the edges be longing to multiple blocks to an appropriate block for fault recovery purposes. Within each block, the working flows are restored in real-time via local p-cycles on the on-cycle and spoke fibers. The performance of the proposed protection framework is evaluated numerically in terms of the spare capacity to working capacity ratio and the length of the restoration path. The framework has a better spare capacity efficiency than existing loopback recovery schemes or the conventional p-cycles approach. In addition, the Star-Block decomposition algorithm shortens the average length of the restoration path and therefore reduces the restoration time. Finally, the protection scheme not only provides a differentiated recovery service for traffic with different QoS requirements in the event of single-link failures within a single block, but also supports multiple-fault restoration for the case in which multiple single-link failures occur simultaneously.

Recently, normal bases have been an appealing technique for hardware implementation in many applications, especially when finite fields are very large, such as the public key cryptosystems. In this article, a new viewpoint is introduced for performing the multiplication in the normal basis representation over binary field where the field defining irreducible polynomial is an all-one polynomial. The proposed multipliers carry out the normal basis multiplication by using extended polynomial basis multiplier to construct two architectures. These two classes of architectures are in bit-serial and bit-parallel which reduce the cost of space and time respectively.