ITM 820 Lecture Notes - Lecture 3: Engineering Notation, Encryption, Access Token
Document Summary
Protocols: it defines some rules, so the communication system works: we need protocols, we don"t know what happening in the back. Are the intellectual core of security engineering. It is where cryptography and system mechanism meets. They also help systems survive malicious acts: confidentiality ex. Price from guests: integrity: ex. cant substitute a cheaper wine, non repudiation: ex. host cant falsely complain. Logon protocols user enters a password into a machine or website (via internet: complex. Such as swiping a badge through a reader in order to enter a building: do not necessarily involve technical measures like cryptography. Attackers came up with a device known as grabber to record a code that was broadcasted locally and replay it later: it was later used to steal cars, it is known as the replay attack. Solutions: generate a 16 bits serial number.