Design of a Hybrid Cryptographic Algorithm Wang Tianfu, K. Ramesh Babu School of Computing Science and Engineering, VIT University, TamilNadu, India 165559672@163.com ; Abstract—Internet is a public-interacted system; the amount of information exchanged over the internet is completely not safe. Protecting the information transmitted over the network is a difficult task and the data security issues become increasingly important. At present, various types of cryptographic algorithms provide high security to information on networks, but there are also has some drawbacks. To improve the strength of these algorithms, we propose a new hybrid cryptographic algorithm in this paper. The algorithm is designed using combination of two symmetric cryptographic techniques. These two primitives can be achieved with the help of Advanced Encryption Standard (AES) and Data Encryption Standard (DES). This new hybrid cryptographic algorithm has been designed for better security with integrity. Keyword:AES, DES, Hybrid, Cryptographic, Security. 1. INTRODUCTION Curiosity is the most common human characteristic. In order to secure the transmission of messages, spies, military and business people sometimes pass misleading information. A key is used in conjunction with a cipher to encrypt or decrypt text. The key might appear meaningful, as would be the case with a character string used as a password, but this transformation is irrelevant the functionality of a key lies in its being a string of bit determining the mapping of the plain text to the cipher text [2]. 1.1 Why need hybrid cryptograph algorithm? A Computer Network is an interconnected group of autonomous computing nodes, which use a well defined, mutually agreed set of rules and conventions known as protocols, to interact with one-another meaningfully and allow resource sharing preferably in a predictable and controllable manner. Communication has a major impact on today’s business. It is desired to communicate data with high security. With the rapid development of network technology, internet attacks are also versatile, the traditional encryption algorithms (single data encryption) is not enough for today’s information security over internet, so we propose this hybrid Cryptograph Algorithm. 2. METHODOLOGIES 2.1 AES Advanced Encryption Standard (AES) is based on a design principle known as a substitution-permutation network[8]. It is fast in both software and hardware. Unlike its predecessor, DES, AES does not use a Feistel network [1]. AES has a fixed block size of 128 bit and a key size of 128, 192, or 256 bit, whereas Rijndael has specified with block and key sizes in multiples of 32 bit, with a minimum of 128 bit. The block size has a maximum of 256 bit but the key size has no theoretical maximum [5]. K Ramesh Babu et al, International Journal of Computer Science & Communication Networks,Vol 2(2), 277-283 277 ISSN:2249-5789