H
ELECTRICITY
H04
ELECTRIC COMMUNICATION TECHNIQUE
H04L
TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
H04L9/00
Cryptographic mechanisms or cryptographic; arrangements for secret or secure communications; Network security protocols
H04L9/06
the encryption apparatus using shift registers or memories for block-wise; or stream; coding, e.g. DES systems; or RC4; Hash functions; Pseudorandom sequence generators
H04L9/0643
Hash functions, e.g. MD5, SHA, HMAC or f9 MAC