Defending systems against viruses through cryptographic authentication

The author describes the use of cryptographic authentication for controlling computer viruses. The objective is to protect against viruses infecting software distributions, updates, and programs stored or executed on a system. The authentication determines the source and integrity of an executable, relying on the source to produce virus-free software. The scheme relies on a trusted (and verifiable, where possible) device, the authenticator, used to authenticate and update programs and convert programs between the various formats. In addition, each user´s machine uses a similar device to perform run-time checking