Protocols

Question 1

Describe how SSL/TLS are used to secure card transactions online

Answer 1

+Browser requests a secure page (https://).

• Web server sends a public key with its certificate

+ Web browser checks certificate is from trusted party

+ Web browser encrypts random symmetric encryption key
using public key

+ Sends it to the server with the encrypted URL and other
encrypted http data.

• Using private key, web server decrypts symmetric
  encryption key
• Web server sends requested html document, http
  data encrypted with symmetric key.

+ Web browser decrypts http data and html document
using symmetric key

+ Displays information/page.

Question 2

Define a protocol

Answer 2

Rules that define methods of communicating data between two or more digital devices, ensuring the transmission of data always follows a protocol.

Question 3

Explain TCP/IP ( Transmission Control Protocol )

Answer 3

Data sent over the internet, it is broken into packets which are separately sent and then reassembled at the desired location.

Question 4

Explain SMTP

Answer 4

Used to transfer emails between mail servers.

Question 5

Explain POP3 (Post Office Protocol 3)

Answer 5

Used to retrieve emails from the mail server, allows us to download messages for offline reading. However you can access and download it on the server once.

Question 6

Explain
HTTP (Hyper text transfer protocol)
HTTPS (Hyper text transfer protocol secure)

Answer 6

Hyper text transfer protocol Allows web server and browser to transfer files over the internet. Allows us to access WWW.

HTTPS is A secure version of HTTP, uses public key cryptography to encrypt communication.