Types of Networks

LAN:

• Local Area Network.
• All devices are connected onto ONE network via a switch.
• No routers are involved.
• Usually only has one owner.
• For example: Homes, schools etc.

WAN:

• Wide Area Network.
• Several networks are connected via routers.
• Both switches and routers are involved.
• Multiple owners.
• For example: the internet.

Transmission Mediums: Wired

A good transmission medium would lose no data when one device sends another device a message.

There are two common types of wired transmission mediums:

• A twisted pair.
• optic.

Twisted pair:

• A twisted pair uses an electrical signal.
• Consists of 2 copper wires twisted around each other.
• One signal goes down one wire and the other down the other wire.

Advantages:

• Inexpensive.
• Flexible.
• Secure.
• Access is controlled.

Disadvantage:

• Limited range - about 90m.

Fibre Optic:

• A fibre optic uses light signals.
• Made of little transparent rods.

Advantages:

• Fast.
• Very long range - about 10,000m.
• Secure.
• Access is controlled.

Disdvantage:

• Expensive.

Transmission Mediums: Wireless

A good transmission medium would lose no data when one device sends another device a message.

Description:

• Signals pass as radio signals.
• Also known as WiFi.
• Devices must have wirless capability, and a wireless acess point.
• Wireless capability could be a USB dongole or a HDMI cable.

Advantages:

• Flexible - can be extended.
• Low cost.
• Fast because radio waves are fast.

Disadvantages:

• Less secure - If someone knows the password you can get in.
• Signals can easily be blocked by large, heavy objects.