Hello,

Can you please tell me what is mean by Data Transfer and Signaling Transfer.Also,please spot out the difference between them.

Regards,
Krishnan.

I would imagine that signalling transfer is for determining when the sending and receiving equipment is ready to accept the data transfer. No point in sending data if the receiver is not ready.

Think of it like a telephone call, you dial a number and start talking without waiting for the phone to be answered.

The dialing tone, ring tone is the signal transfer, the data transfer happens when the call is answered.

Ok... Now let me take a situation in which you are connected to 20 lines in an office via a central phone that is going to receive any external calls... You have to receive the external call and transfer it to the respective phone who is the intended receipient... please explain the scenario of call and data transfer that takes place at this juncture...

Presume it is a computer network:

Calling computer "calls" the exchange: Signal Transfer
Exchange computer "answers" call: Signal Transfer

Calling computer sends requested extension: Data Transfer
Exchange computer processes call

Exchange computer "checks" if extension is busy: Signal Transfer
If OK, exchage computer connects caller and extension

Computer communicate: Data Transfer

It works the same for voice calls via an operator.

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