Compression and Encryption

Question 1

Run Length Encoding:

Answer 1

Works for grouping repeated values

Question 2

Dictionary Encoding

Answer 2

Frequently occurring pieces of data are replaced with an index

Question 3

Encryption types

Answer 3

Symmetric: Both the sender and the receiver have the same private key which they exchange in a key exchange.
Asymmetric: Encrypted with a public key, decrypted with a private key

Question 4

What is Hashing:

Answer 4

An input (key) is turned into a fixed value size, which cannot be reversed
The hash correlating to the key is stored in a hash table
If 2 keys have the same hash, a collision happens, they could be stored in a list or use a second hashing function

Question 5

What are collisions and how to prevent

Answer 5

If 2 keys have the same hash, a collision happens, they could be stored in a list or use a second hashing function