Unit 5 Fundamentals of networks

Section 5 - Fundamentals of computer networks

Wired and wireless networks

The internet - biggest network that spans the entire world

WAN (Wide area network) - Spread over a wide area, usually cost a lot, and are usually owned by 1 or a few organisations. 

An IP address is an address given to a computer based on where it is located

Packet switching - A file is broken down into smaller files and each is given an address of where it has to go and where it came from, a number for what order it comes in and the number of packets in the whole communication. Packets are all sent across different routes to reach the destination, and then they are reassembled at the destination

The hardware required for a network includes routers, switches and network interface cards (NICs)

Router - routes packets across a WAN like the internet, sending them between several routers

Switch - Used to route packets in LANs. The switch knows the mac address of everything connected to it, so it can send packets directly to the address without it being sent to an unintended recipient 

NIC - required to connect any network enabled device. Can either be connected wirelessly or using an ethernet cable. Each NIC has a MAC address assigned to it. No device has the same MAC address

Wireless networking

Networks can use WiFI connection, WIfi is a family of protocols that make wireless networks run smoothly

Advantages

• Users can move around with portable devices and can still be connected

• Users can share files without having to be physically connected

• It saves the expense and time of physically connecting everything together

• You can add a new device easily

• Instant transfer of data is quicker

Disadvantages 

• File transfer speeds are slower

• Wireless connections can be obstructed by walls

• Less secure and can be easier to hack

• Confidentiality can be lost

Network topologies and transmission

Local area networks (LANs)

Covers a small area, and connects everything together. LAN is often owned by a single organization like a school

Benefits

• You can share resources and devices easily

• Everything is managed centrally

• Easy to update the entire system

Disadvantages

• If the network goes down, no one can access the files

• If the network traffic increases, performance degrades

• Difficult to keep it safe from hackers

• Viruses can easily spread

• The bigger the network, the harder it is to manage

Network topologies

Star topology 

All of the computers have their own cable connecting to a switch.

They are…