Patent · US Expired

Synchronization of encryption/decryption keys in a data communication network

US5805705A · kind A · utility

99Cited by
5References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1996
Grant dateSep 8, 1998
Priority date
Expiry dateJan 29, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L69/22
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

To enhance the security provided by data encryption in a data communication network, the encryption/decryption keys are changed periodically at the source and destination nodes for an established connection. A destination node must know not only the value of any new key but also when to begin using that key to decrypt received data packets. Synchronization (making sure a data packet is decrypted using a decryption key correlated with the encryption key used to encrypt the same packet) is achieved by defining a single bit in each packet header as a key synchronization bit. As long as key synchronization bit value remains unchanged from one received packet to the next, a receiving node will continue to use the same decryption key it has been using. When a change in the key synchronization bit value is detected, the receiving node will begin using a previously-received, new decryption key.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.