So what’s a good hash function? • Heuristic, good when keys are uniformly distributed! • Idea! Don’t use a fixed hash function! Choose one randomly (but carefully)! Universal (good, theoretically): • Why is …

h(key) is known as the key's hash code. A collision occurs when items with different keys are assigned the same hash code. Each position in the hash table serves as a store multiple data items. When the …

What is a hash function? Hash functions play a fundamental role in cryptography. They are used in a variety of cryptographic protocols. They are difficult to design because of stringent requirements. H is …

A cryptographic hash function has the same properties as ordinary hash functions: it is easy to compute, takes an arbitrarily long input string (or file), and it produces a random-looking, fixed-length, output …

Perfect Hashing (for static case) We say a hash function is perfect for S if all lookups involve O(1) work.

SHA-224 and SHA-384 are simply truncated versions of SHA-256 and SHA-512 using different initial values. 1. Append padding bits. 2. Append length. SHA-1 produces 160 bit output, SHA-224, SHA …

Designing hash functions is beyond the scope of CS106B! But in the second half of this lecture, we’ll discuss how to use them.