Secure composition of protocols

Abstract

Security protocols are small distributed programs that are designed to ensure security over untrusted networks such as the Internet. They are notoriously dificult to design and flaws can be found several years after their publication and even their deployment. In particular, they are not securely composable in general: two protocols may be secure when analyzed separately but may cause harmful interactions to each other. We explore how tagging protocols allows to securely compose protocols.