Methods and apparatus for secure data communication links

摘要

This invention generally relates to methods, apparatus and computer program code for secure communication links, in particular where accountability is required. A method of initialising a secure communications link between a first data processing system and a second data processing system using a first token comprising a first key and associated first request data is described. The method comprises: generating at said first system a first message comprising said first token and first authentication data generated by operating on at least one of said first key and said first request data with a secret key of said first system; encrypting said first message using a key known to both said first and said second data processing systems to form an encrypted first message; and sending said encrypted first message from said first system to said second system to initialize said secure communications link. The method is particularly useful for establishing chains of accountability in systems where trust is delegated.