COM UNIT2 AOS2: Network Security

Exam and written SAC revision

LAN (Local Area Network)

It’s a network of computers within small area like room, buildings or colleges. LAN where wireless media are used is known as Wireless Local Area Network

WAN (Wide Area Network)

WAN is a a network of a computers in a wide geographical area such as a country, neighboring countries continent. A WAN can be formed by joining LANs. E.g. the internet is the largest WAN.

WPAN (Wireless personal network)

A personal area network is a computer network for connecting individuals within a limited range.A WPAN is a type of personal network that uses wireless transmission media to transfer data between a users personal device.Common devices found within a WPAN includes laptops, smart TVs, wearable tech, phones and speakers.

Network Architecture

Specifies how computers on the networks interacts and communicates with each other.

Client Server Network

• Computers are connected to a central server and communication is done through it.

• Server is the main computer and gives services to the work station

• Serve runs the NOS (network operating system) controls LAN

Peer to Peer Network

Every computer in the network has equal right

Does not contain a file server to control the LAN

Has trust in the users and a small number of users

Virtual Private network (VPN)

A network that is constructed by using the internet to connect to a private network, such as a company’s internal network.

NIC (network interface card)

Is a component of the computer which allows it to connect to the network and “interface with it”

Hub

Serves as a central connection point for multiple computers and devices linking them together in a LAN.

Switch

A switch can read the address of of the data and send the data to the correct device. Like traffic lights.

Connectors

cables and connectors are used to transfer data

Routers

Routers used to connect to other networks also may allow wireless access to the network.

Wireless Access Point

any point which you can access a network E.g. modem or router

File Server

Server specifically set up to share documents and digital resources e.g. videos, programs

Network Protocol

Established set of rules that dictate how to format, transmit and receive data so computer network devices can communicate regardless of the differences in their underlying infrastructures, design.

TCP/IP

The TCP/IP (Transmission Control Protocol/Internet Protocol)

is a set of rules that allow communication between two

networked devices.

DDoS

a DDoS attack is an attack in which multiple compromised computer systems attack a target, such as a server, website

Security Threat

Anything that has potential to cause harm to data and information stored and in communication between information systems.

Malware

software that is specifically designed to disrupt, damage, or gain unauthorized access to a computer system.

Virus

A computer program that reproduces it self on the same computer

Worms

Is a self replicating malware that can spread across computer systems, which can modify, corrupt or detect data and information

Trojans

Take the form of ‘free virus checking software’ when in fact they are malware and can be virus propagators

Spyware

Collects data about a users activity and sends that data to another location without the users knowledge

Brute Force Attacks

Making repetitive attempts to access an information system using variations of possible usernames and/or passwords

Encryption

Involves encoding or changing data so that it can only be decrypted by the receiver if they have the correct key.

Encryption Key

A series of bits that is used to apply an algorithm to the data packets to scramble and unscramble the data.

Symmetric Encryption

Both sender and receiver use the same private key. Sender encrypts using that private key and the receiver decrypts using that private key.