Patent ID: 9282082
Filing Date: 2016-03-08
CPC Classification: G06F,H04L

Claim Text:
1. A method of compressing and decrypting encrypted data, wherein said encrypted data is obtained by selecting one message from a group of M messages and encrypting the selected message using block ciphers in a chained mode of operation to form a first encrypted message, the method comprising: compressing the first encrypted message by truncating the first encrypted message to obtain a first truncated encrypted message; and decompressing and decrypting said first truncated encrypted message to obtain a decompressed and decrypted message by encrypting all of said M messages to obtain a series of encrypted messages, wherein each of the series of encrypted messages is formed from one of the M messages, truncating each of said series of encrypted messages to obtain a series of truncated encrypted messages, and comparing the first truncated encrypted message to each of said series of truncated encrypted messages, using defined criteria, to match one of said series of truncated encrypted messages to the first truncated encrypted message, and declaring the one of said M messages from which the matched one of the series of truncated encrypted messages is formed, as the decompressed and decrypted message.