Computing - 5 Fundamentals of Computer Networks - 3 Network Security

Network security methods [4]:

- authentication
- encryption
- firewall
- MAC address filtering

Authentication

verifying the identity of the person or device attempting to access the system

Examples of authentication [4]:

- password
- pin pattern
- facial identification
- fingerprint

Encryption

process of converting readable data into unreadable characters to prevent unauthorised access

Types of encryption [2]:

- symmetric encryption
- asymmetric encryption

Symmetric encryption

encryption method where the same key is used to encode and to decode the message and this key must be transferred

Asymmetric encryption

two keys are used - one public key to encode the message, and one private to decode it

Caesar cipher

substitution cipher that shifts characters a certain number of positions in the alphabet

Wireless encryption standards [2]

- WEP
- WPA

WEP stands for...

Wired Equivalent Privacy

WPA stands for...

Wi-Fi Protected Access

Why must data be encrypted?

it could be intercepted while being transmitted over a network

HTTP stands for...

Hypertext Transfer Protocol

HTTPS stands for...

Hypertext Transfer Protocol Secure

Hypertext Transfer Protocol

set of rules for transferring data from web servers to browsers

Hypertext Transfer Protocol Secure

extension of HTTP where data is encrypted so it can be transferred securely

'Strong' encryption

useful lifetime of encrypted data is less than the time taken to break the code

'Weak' encryption

code can be broken in time to use the information

Firewall

software or hardware on servers that only allows traffic through according to some set of security rules

Firewall capabilities [5]:

- monitor network traffic
- allow or block traffic depending on filtering rules
- prevents access by attackers to networked computers
- blocks certain malicious computers using packet filters
- prevents access to certain network ports

Packet filter

detects and blocks data packets from malicious computers using an IP address

MAC address filter

filter built into wireless routers that can block certain devices using their MAC address