Public Key Infrastructure

Question 1

PKI public key infrastructure

Answer 1

Policies, procedures, hardware, software that is responsible for creating, distributing, manage, storage, revoke processes associated with digital certificates. This is everything what you have to do with encryption in your company. Also a way to associate a certificate for people or device. This is conjunction with certificate authority and all about trust.

Question 2

Symmetric encryption

Answer 2

There is single shared key. Encryption is with this key, and decryption is with the same key, when this is out you need new key. Also described as a secret key algorithm, where symmetric key is that one secret key (shared secret). Challenging to distribute. Is still used, is very fast often combined with asymmetric encryption.

Question 3

Asymmetric encryption

Answer 3

Is decrypting with two different keys, which ale mathematically related. Private key - one person on one device will have access to it. Second key is public key where anyone can see this key and use this key. Someone is encrypting data using your public key, but your private key can only decrypt the data. There is no option to calculate someone’s private key when you have someone’s public key.

Question 4

Key pair

Answer 4

This is public and private key, both are created in the same time. Process of: randomization, large prime numbers, lots of maths behind the scene.

Question 5

Asymmetric encryption example

Answer 5

X has public an private key => Y message (plain text) and encrypted by X public key => ciphertext creation => ciphertext sent to X => X encrypts data by his private key => initial plain text visible