wan the internet and protocol lesson objective: understand the main terminology about networks. ...
TRANSCRIPT
WAN the internet and protocol
Lesson Objective:Understand the main terminology about networks.
Learning Outcome:Understand the different types of network and the advantage of each.
Wide Area Networks are usually spread out geographically.
The organisation usually owns and maintains the network equipment for a LAN, but the equipment used to make the WAN is owned and maintained by another organisation.
An example of a WAN. A company may have several international offices, they each have their own LAN.
Each computer on the LAN can communicate to others far away using a WAN
Connecting to the internet
ISP
The Internet
Modem or Router
The ISP services
…Plus others …eg.Video conf.Virtual Network
The two main uses of the internet.
Communicating with a modem or router
Digital data is stored as 0’s and 1’s
Digital information occurs in steps
Analogue information makes gradual changes
Analogue data can be stored as writing, sound, …etc.
What’s this?
MODEM
MOdulator
DEModulator
Answer questions about what equipment is used to transfer data and how it is done.
What does the Modem do?Data on the sending computer
Data on the receiving computer
The modem converts the digital data to analogue sound waves.
Sound waves transmitted.
The modem converts the analogue sound waves to digital data.
Examples of digital communications
Fax
Video conferencing
What information is communicated?
IP Address:34.165.233.23
IP Address:52.43.234.192
IP Address:133.15.233.123
Each computer on the internet has a unique IP address. It is made up of four 8 bit bytes.
DNS (Domain name server)
DNS Server
What’s the ip address of www.bbc.co.uk?
212.58.246.90
212.58.246.90
Like using a phone bookto look up a number.
Protocol
Protocol is the way in which information is communicated
Protocol will break down this information into something useful
10011010101110100100010100100011010110101010101101001
10011010101110100100010100100011010110101010101101001
Send this informtion to 143 . 34. 145.183 Hello how are you …
Packets
Information on the internet (an on many LAN networks) is sent in packets
Packets are used so that no single computer can prevent other computers from ‘hogging’ the network.
Sending packets