05303303 is referenced by 60 patents and cites 2 patents.

Data is encrypted for transmission over non-secure communication by providing data with a header and a trailer portion containing the full information as to the sender and recipient of the data so as to form a data packet, incrypting the data packet, and providing a further header and trailer portion to form a further data packet. The further header and trailer only contain information identifying the entry and exit nodes at which the further data packet enters and leaves the non-secure network. On arrival at the exit node the further data packet can be decrypted to reconstruct the original packet which is then conveyed to its destination via a local secure network. Padding non-secure network with dummy messages makes it impossible to identify the presence of genuine traffic between particular nodes of the non-secure network. Thus secure data may be sent via commercial non-secure packet switching networks without indicating its presence.

Title
Data communication system using encrypted data packets
Application Number
7/988112
Publication Number
5303303
Application Date
February 8, 1993
Publication Date
April 12, 1994
Inventor
Andrew R White
Harrow on the Hill
GB
Agent
Lowe Price LeBlanc & Becker
Assignee
GPT
GB
IPC
H04K 1/00
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