IB Digital Society - Paper 1 - Section 3: Content (3.4: Networks and The Internet)

Key terms for Topic 3.4: Networks and The Internet for the IB: Digital Society course.

Network

Network

A series of interconnected nodes (connection points) that transmit, receive and exchange data, which can range from text, sound to video.

Network size: Personal Area Network (PAN)

• The smallest type of network, consisting of connected devices in close proximity to an individual.

• Example: wirelessly connecting to a phone

Network size: Local Area Network (LAN)

• A group of computers or devices connected on a single site, which is set up to help the sharing of resources.

• Example: giving access to a printer at home

Network size: Metropolitan Area Network (MAN)

• Network that covers a larger geographical area, ranging from 5 to 50 km. 

• Example: Cities that provide free wifi (New York City)

Network size: Wide Area Network (WAN)

• The largest type of network, which is commonly used by businesses through a collection of LANs.

• Example: Internet - largest available WAN, a collection of networks and networking technologies which connects users.

Connectivity: Wired Networks

Devices connected with copper ethernet cables which plug into an ethernet port (which were either integrated onto the motherboard or installed as a separate interface card).

Connectivity: Wireless Networks

Devices embedded with wireless network interface cards connect either through a wireless access point or router.

Connectivity: Cloud Networks

Incorporate some or all network capabilities to a cloud platform.

Sharing Data: Client-server Network

Data is stored centrally on a server and access is granted to connected devices (also referred as ‘clients’).

Sharing Data: Peer-to-peer Network (P2P)

A decentralized network - each device is equally responsible for sharing and storing data.

Components: Network interface card

A device (typically a circuit board or chip) which is responsible for converting data into a digital signal and communicating this data to a network.

Components: MAC address

Media Access Control Address - a unique number assigned to every network device.

Components: Router

A networking device which connects two or more separate networks.

Components: Modem

A device which converts digital data into analogue data.

Components: Wireless access point (WAP)

A device that creates a wireless local area network to improve coverage throughout a building.

Components: Hub

The most basic and cheapest network device - when it receives data, it re-broadcasts the data to all connected devices.

Components: Switches

A more upgraded version of hubs - they inspect data they receive before sending it to the intended recipient.

Network Protocol

• A set of rules which outlines how data is sent, formatted and received.

• The protocols include different layers which govern different parts of a communication.

Network Protocol: Application Layer

A set of protocols used by applications.

Network Protocol: Transport Layer

Oversees communication between hosts using the Transmission Control Protocol/Internet Protocol (TCP/IP) is a set of rules which governs how data is sent within a network

Transport Layer: Transmission Control Protocol (TCP)

Ensures data is sent and received correctly. TCP needs to make a request if data is lost in order to re-send it.

Transport Layer: Internet Protocol (IP)

Deals with the addressing of individual devices and routing data.

Network Protocol: Internet Layer

Concerned with the sender and the recipients’ IP address. Additionally, it routes the data packets across a network.

Internet Layer: IP (Internet Protocol) address

A numeric address assigned to every node (device) which identifies them within a network.

Internet Layer: Dynamic Host Configuration Protocol Server (DHCP)

Assigns an IP address, to avoid address conflict (having more than one device with the same IP address number) and to keep track of each assigned number.

Network Protocol: Physical Network Layer

Protocols which allow different networking technologies to work together.

Network Protocol: Domain Name Server (DNS)

A server which translates the domain name into IP addresses. The server searches for an IP address in its database and will forward data to that address.

Capacity: Bandwidth

The amount of data a network can transfer at once. It is measured in hertz (Hz).

Capacity: Speed

The length of time it takes for data to be transferred. It is measured in megabits per second (Mbps).

Capacity: Data Compression

• Process which reduces size of a file by re-coding it with fewer bits of storage.

• There are two types of compression algorithms: Lossy Compression and Lossless Compression

Data Compression: Lossy Compression

Reduces file size by permanently removing unimportant data.

Data Compression: Lossless Compression

Reduces file size but without losing data and the possibility of turning the file to its original data.

Security: Authentication

The most basic form of security, whereby a users uses a unique username and strong password.

Security: Multi-factor Authentication

• More reliable, a user is requested to give two or more credentials, which can include a mix of physical or biometric measures.

  • Examples:

    • Physical Measures - token, card or text message

    • Biometric Measures - faceprint, PIN or phrase

Security: Firewall

A hardware or software which inspects incoming and outgoing data to determine which data is allowed to enter the network.

Security: Proxy server

A computing system which acts as an intermediary between the client on the network and the internet.

WWW: URL

Unique Resource Locator - a unique address for each resource on the web, which can include the address of a web page or a file hosted by a web server.

WWW: HTTP or HTTPS

Determines how web resources are transmitted between the web browser and the web server.

WWW: HTML

Format of web pages - allows documents to be displayed as web pages and web pages to be linked together. 

Evolution: Internet of Things (IoT)

• Refers to all devices which are connected to the internet - this does not only include phones or laptops but also smart appliances and autonomous vehicles.

• Example: Smart door lock

Dilemmas: Spamming

Sending unsolicited emails with the purpose of advertising.

Dilemmas: Hacking

Defined as the unauthorized access to a computer or network.

Hacking: Social Engineering

An umbrella term to refer to all techniques aiming to obtain user’s data, which normally trick a user into sharing credentials (username and passwords).

Social Engineering - Types: Phishing

Hackers send fraudulent emails designed to trick users into revealing sensitive information.

Social Engineering - Types: Viruses

A type of malicious software (or malware) composed of small pieces of code. It is attached to legitimate programs or emails.

Social Engineering - Types: Ransomware

A malware which locks a user out of their device, demanding a payment to release them.

Social Engineering - Types: Distributed Denial Of Service (DDOS)

An attack were a network of computers with malware (botnet) disrupts the normal traffic of a site or service, making it unavailable to intended users.