1.3.1 Compression, Encryption and Hashing

Question 1

What is symmetric encryption?

Answer 1

An encryption method whereby the same private key is used to encode and decode the message

Question 2

What is Asymmetric Encryption?

Answer 2

a type of encryption that requires 2 keys - one of which is secret (or private) and one of which is public (freely known to others).

Question 3

What is run length encoding?

Answer 3

A lossless compression algorithm that represents an image in terms of the length of runs of identical pixels

Question 4

What is dictionary encoding?

Answer 4

Uses a dictionary (index number, its binary, a word) to replace texts with shorter binary strings by representing the words as numbers and then referencing to the dictionary to find the correct word

Question 5

What are some uses of hashing?

Answer 5

-Passwords
-Digital signatures
-Digital certificates
-Hash tables