On the security of public key protocols

TLDR

Public key encryption is widely used for secure network communication, protecting against passive eavesdropping but potentially vulnerable to active attackers who can impersonate users or tamper with messages. The authors develop formal models and provide algorithms and characterizations that enable precise assessment of protocol security within these models.

Abstract

Recently the use of public key encryption to provide secure network communication has received considerable attention. Such public key systems are usually effective against passive eavesdroppers, who merely tap the lines and try to decipher the message. It has been pointed out, however, that an improperly designed protocol could be vulnerable to an active saboteur, one who may impersonate another user or alter the message being transmitted. Several models are formulated in which the security of protocols can be discussed precisely. Algorithms and characterizations that can be used to determine protocol security in these models are given.