Public Key Infrastructure C3B

Question 1

Mechanisms to Protocols

Answer 1

A protocol is an orderly sequence of steps that two or more parties follow to accomplish conjoint tasks.

Question 2

Repetitive vs Random

Answer 2

Repetitive - an attacker could intercept a daily encrypted message that was always nothing to report
Random - an attacker just waits for the day the ciphertext becomes different from before

Question 3

Public Key Crytography

Answer 3

Asymmetric algorithms allow you to generate a key pair.
- The private key never leaves your hard drive.
- The public key is published far and wide.

Question 4

Mechanisms to Protocols: Digital Signatures

Answer 4

A digital signature is itself a sequence of bits conforming to one of a few standards.

Question 5

Mechanisms to Protocols: Session Keys

Answer 5

• Generate a symmetric ‘session key’
• Used only for this communication session
• Random number
• Use public key to encrypt
• Then use the session key to exchange data

Question 6

Security Protocols: Man-in-the-middle Attack

Answer 6

• it occurs when public keys all look the same, and people exchange keys directly
• Digital Certificates are used to assure authenticity of the sender.
• Issued by third parties: certificate authorities (CA).

Question 7

Certificate Authority (CA)

Answer 7

The CA is the final result in a long linkage of developments in applied cryptography that attempt to solve the problem of authentication.
- The CA solves the problem of authentication by trusted referral.

Question 8

Secure Socket Layer (SSL) and Transport Layer Security (TLS)

Answer 8

1. Application
2. SSL
3. TCP (transmission control protocol)
4. IP (Internet Protocol)
5. Data Link

Question 9

SSL (Secure Socket Layer)

Answer 9

SSL is standard technology for securing an internet connection by encrypting data sent between a website and a browser (or between two servers)

Question 10

TLS (Transport Layer Security)

Answer 10

facilitate privacy and data security for communications over the Internet