%0 Journal Article %T DEDD Symmetric-Key Cryptosystem %A Praloy Shankar De %A Prasenjit Maiti %J International Journal of Advanced Computer Research %D 2013 %I Association of Computer Communication Education for National Triumph (ACCENT) %X Now a days the greatest challenge to the cyber worldis security. We need more and more security for ourunsecured systems because technology is not aconstant factor. There are lots of catalysts, canbreak the securitysystem. Day by day number ofhackers is being increased.Existing old methods ofsecurity often fails to overcome it. But as an ancientquote says it¡¯s true that ¡°Old is Gold¡±, thosemethods help us to develop a new idea to sort outour problem in situ thus leads us to discover a newhorizon.In this paper an attempt has been made tofocus on an algorithmof cryptography that wasmadebyusingold methodologies.DEDDsymmetric-key cryptosystem is the new approach tosymmetric keyalgorithm. By this method we candoubly encrypt and doubly decrypt the message.Itmeans thesender will generate the cipher text fromthe plain texttwice.Thereceiverwillalsohavetodecrypt theciphers for two times and thenthecommunicationbetween themwill be completed.For generating the key,we willtake the messagelengthin first encryptionand insecond encryptionwe will apply shifting techniqueon a methodintegrate_expo which calculates the value ofe^integration (m^k dm) from limit m=0 to limitm=m1(message length) where e=exponential,m=variable.Double de-cryption will be done by thereverse process ofencryption techniques. There arelots of algorithms for symmetric key cryptographylike DES, AES,BLOWFISH, andHMAC-MD5etc. %K Double Encryption and Decryptio n %K Symmetric - key cryptosystem %K Cipher %K Key generation . %U http://www.theaccents.org/ijacr/papers/conference/icacc2013/30.pdf