1.3.1 (c) Symmetric & Assymmetric Encryption

What are the two different types of encryption?

• symmetric

• asymmetric

What is encryption?

process of encoding a message so it can be read only by sender & intended recipient

What is symmetric encryption?

sender & receiver have the same private key (key used for both encrypting & decryption message)

What are advantages of symmetric encryption?

• simple to implement

• efficient & faster for large data than asymmetric as it is less complex

What are disadvantages of symmetric encryption?

• single point of failure - if private key compromised attacker can decrypt easily

• not scalable for large networks

What is asymmetric encryption?

sender and receiver have unique keys (key pair):

• public key - anyone can access, encrypts message

• private key - only recipient has access, unlocks content, decrypts message

What are advantages of asymmetric encryption?

• secure w/o needing to share private keys

• enables data signatures - verify sender’s identity & ensure data hasn’t been changed

What are disadvantages of asymmetric encryption?

• slower for large data

• computationally expensive

What is hashing?

a function that transforms a string of character into a fixed-length value/key that represents the original

How is hashing different from encryption?

one way process - hash function can’t be reversed to form the key

What are uses of hashing?

• storing passwords

• digital signature - verify sender’s identity & ensure data hasn’t been changed

• hash tables - data structure that holds key pairs

What is a collision in term of collision?

when two different inputs produce the same hash value

How can a collision be prevented?

salting - adding a random value to the password before hashing it

What are advantages of hashing?

• irreversible - very secure for storing private data

• enables integrity checks - can be used to verify data hasn’t been altered

What are disadvantages of hashing?

• vulnerable to brute-force attacks

• collision risks if algorithms are weak