data exchange

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Simplex is data transmitted in one direction only.This data is received by your tv which then carries out the request like turn the volume up or change the channel. half duplex is when devices can communicate with each other but only one at a time.Full duplex is like your telephone. You and your friends can speak to each other at the same time. The data channel allows 2 way communication.

paralell and serial transmission

serial data transmits data 1 bit at a time.

paralell data transmists data 8 bits at a time.

server side processing: scripts of code that runs on your machine but the information is submitted to a webserver which then does all the powerful processing. example is the Google search. You open Google and search for Portland Ale. Your request is sent to Google's servers which then process it and look up the gigantic database of websites.

Advantages: server is more powerful than your client so it can run very complex codes quickly.doesn't matter whether you are using Chrome, Explorer or Safari.server can process your request much quicker than your client as it will be more powerful.

disadvantages:Overloading - if one server gets lots of requests at once, it can overload it.

Client Side Processing:example of client side processing is a rollover image. You might have created these if you have done the website unit.

When you move your mouse over a picture, it changes from one picture to another. The code that does this is within the website and is therefore run ON THE CLIENT

ADVANTAGES ARE:

Speed - because the code is on the client, it runs very quickly. It doesn't need to be fetched from the server to run.

Security - because the code runs on the client it isn't passing over a network and is therefore less likely to be intercepted.

DISADVANTATES ARE:

Browser dependent - it does matter what browser you are on. Some code won't work on some browsers. For example there may be issues processing code in Explorer compared to Safari.

Computer speed - if your computer is old and as slow as a donkey, the code in the website might take a long time to run.