Fundamentals Of Computer Networks Flashcards
What is a network?
Network is an interconnection of computers and other clients to facilitate communication and the sharing of resources
What are the 3 types of networks?
PAN - Personal Area Network are devices owned by a single user connected via Bluetooth
LAN - Local Area Network covers a building or campus owned by a single organisation
WAN - Wide Area Network spreads over large geographic area with shared ownership (Internet)
Advantages
Wired and Wireless
Wired networks are more secure and less prone to interference.
Wireless networks are easier to add devices and are portable.
What medium do wireless networks communicate?
Radio Waves
What medium do wired networks communicate?
Optical fibre are used for fast connections for many computers sharing 1 connection.
Copper cabling is cheaper and slower although it is quick enough for most activities.
What is a network topology?
A network topology is the pattern in which hardware on a network is structured including connections. The 2 most common are star and bus.
What is the star topology?
Advantages & Disadvantages
Star topology is where every device is connected to a switch at the centre of the network.
Very few data collisions; Strong, centralised security
Lots of cabling needed, Adding another device can be difficult
What is bus topology?
Advantages & Disadvantages
A central cable called the backbone run between two terminators and connects all devices across the cable.
Uses little cable making it cheaper; Easily adds devices
Collisions can occur; Transmission slow with many devices
What is a protocol?
A set of rules that governs how a computer communicates on a network. Computers have protocols necessary for different purposes.
What are the 10 protocols?
Ethernet
Wi-Fi
TCP/IP
UDP
HTTP
HTTPS
FTP
SMTP
IMAP
What is ethernet?
Family protocols governing how data is formatted in transmission across LAN.
Wi-Fi
Rules controlling how data is transmitted on WLAN
TCP/IP
Transfer Control Protocol
Internet Protocol
2 protocols breaking up data into packets each of which knows where it started and will end an through what medium
UDP
User Datagram Protocol
Protocol transmits packets quickly without checking if each packet has arrived
HTTP
Hypertext Transfer Protocol
Set of rules governing how hypertext is moved around the internet from device to device
HTTPS
HTTP Secure
Encrypts data sent across the internet
FTP
File Transfer Protocol
How files are moved from 1 computer to another across the internet
SMTP
Simple Mail Transfer Protocol
Used to send emails and files from 1 server to another
IMAP
Internet Message Access Protocol
Allows multiple devices to access the same email account
What is IP address?
A unique number used to identify every device connected to the internet. IP address helps specify where a web page should be delivered
How do organisation’s keep data safe?
Authentification, Encryption, Firewalls, MAC Address Filtering
What is the TCP/IP model?
A series of protocols that work together to transmit data from 1 computer to another through anything.
What are the 4 layers of the TCP/IP layer?
Application Layer
Transport Layer
Internet/Network Layer
Network Interface Layer
What is the application layer and what protocols come under it?
Where network applications operate
HTTP, HTTPS, FTP, SMTP, IMAP
Transport Layer
Establishes communication between sender and recipient agreeing how communication will take place
TCP, UDP
Internet/Network Layer
Packages data for transmission into packets which are sent across the network
IP
Network Interface Layer
Hardware such as the network interface card operate at this level
Ethernet, Wi-Fi
