ITM 301 Lecture Notes - Lecture 17: Secure Hash Algorithms, Hash Function, Sha-1

• School: Ryerson University
• Department: Information Technology Management
• Course: ITM 301
• Professor: Farid Shirazi

Document Summary

Hashed data: data that has been transformed through a particular algorithm that generally recurs the amount of pace needed for the data . Can only be retrieved by comparing it with known data. Which receives the same hash funtion and then produces the same hash output - if output does not match, this indicates data has likely been altered. Sha (secure hash algorithm: advantages over md5 is resistance to collisions, original sha - used 160-bit hash function - structured simi- larly to. Md5, was quickly replaced by the next, slightly modified version, Sha-1 has also since been retired in favor of the next two iterations of sha, although many systems still rely on sha-1. Sha-2 sports a variety of hash sizes: most popular are sha-256 (256 bit hash) and sha 512) (512 bit hash) It"s also common for data to be hashed in multiple passes, along with encryption passes layered in to the process.