04-05-2012, 12:59 PM
REAL TIME SECURITY
REAL TIME SECURITY.pptx (Size: 429.13 KB / Downloads: 31)
Cryptography operationsa
Cryptography:
Cryptography deal with data encryption and decryption and
The functionality for this is hide information
Operations:
Encryption
Decryption
Message Digest Algorithm
The algorithm takes as input a message of
arbitrary length and produces as output a 128-bit
message digest. The input is processed in 512-bit
blocks.Several steps involved in this algorithm
Steps for MD5
Append padding bits
Append length
Initialize MD buffer
Process message in 512-bit (16-word)
Secure hash algorithm
The algorithm takes as input a message with a maximum length of less than 264bits and produces as output a 160-bit message digest. length and chaining variable length of 160 bits. The processing consists of the following steps:
Steps for SHA
Append padding bits
Append length
Initialize MD buffer
Process message in 512-bit (16-word) blocks :
COMPARISION OF SHA-1 AND MD5
Security against brute-force attacks
Security against cryptanalysis
Speed
Simplicity and compactness
Little-endian versus big-endian architecture
CONCLUSION
cryptography plays an essential role in protecting the privacy of electronic information against threats from a variety of potential attackers.