Lecture 13
Cryptography is both some complicated math and a core technology in cyberspace. Similarly to all other security mechanisms it is important to understand what it actually does and when it is suitable to use it.
Being able to authorize and idenfity people or other entities is a corner stone in any secure system. User authentication is normally based on (a combination of) something you know, something you have, or something you are.
Security protocols are used when different entities in a secure system communicate. Similarly to most security, the protocols are also based on certain assumptions regarding, for instance, the environment in which it is used and the trustworthiness of the participating entities. One possible use of security protocols is to exchange keys used in cryptography. During the lecture, we will study some protocols that forms the foundation on which today's security protocols are based.
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Reading
Intensive reading: Distributed Systems, 7.2 - 7.6.3
Exercises
Primary set: 7.3, 7.10
Secondary set: 7.4, 7.6, 7.9