Computing - 5 Fundamentals of Computer Networks - 1 Wired and Wireless Networks

Internet

a group of interconnected networks

World Wide Web (WWW)

information system of interlinked web pages and other resources stored in a web server

Web page

document stored on the World Wide Web

Web server

computer that delivers requested web pages to your computer or mobile device using HTTP

Web browser

a software application for retrieving, presenting and traversing web pages

Examples of web browsers [4]:

• Chrome

• Safari

• Edge

• Firefox

WAN stands for...

Wide Area Network

Wide Area Network

computer network that covers a large geographical area using a third party infrastructure

How does a WAN connect remote locations? [4]

• cables

• telephone lines

• satellite

• radio waves

IP stands for...

Internet Protocol

IP address

unique number assigned to any item that is connected to the Internet

IP address format

four 8-bit numbers separated by dots

Circuit switching

a dedicated connection is formed between two points and the connection remains active for the duration of the transmission

Packet switching

data is broken into a number of 'packets' that are sent independently and reassembled at the destination

Packet

512 bytes of data to be sent separately over a network

Packet header contents [5]:

• source IP address

• destination IP address

• sequence number

• number of packets overall

• error checking data

Node

connection point among physical network devices

Examples of nodes [3]:

• router

• printer

• switch

Router

node that forwards data packets across a network

NIC stands for...

Network Interface Card

Network Interface Card

card installed in a computer that allows you to connect to a network

MAC stands for...

Media Access Control

Media Access Control address

hardware address that uniquely identifies the NIC of each node on a network

MAC address format

48 bits (6 bytes). Often displayed as 6 groups of 2 hexadecimal digits separated by colons

Switch

computer networking device that connects nodes and performs packet switching

Hub

computer networking device that connects nodes together

Switch vs. Hub [2]

• HUB transfers data to every connected device

• SWITCH identifies destination MAC address and transfers only to specific devices

Wireless network

any type of computer network that is not connected by cables of any kind

Wi-Fi

wireless method of transferring information using radio waves

What obstructions is Wi-Fi susceptible to? [3]

• objects

• nearby electronics

• other wireless devices

WAP stands for...

Wireless Access Point

Wireless Access Point

enables devices to connect to a wireless network to communicate with each other using Wi-Fi

How does AP connect to a router?

wired network

Wireless NIC

every device capable of connecting to a wireless network has a wireless NIC that connects a computer to a network using radio frequencies

Wireless advantages [3]:

• no cables laid

• new devices easily connected

• devices portable within range of AP

Wireless disadvantages [4]:

• less reliable than wired networks

• connection is slow if many devices connect to AP

• connection speed reduces further from AP

• less secure than wired network