Are you getting disconnected from net when you get an incoming call or someone picks up the phone receiver ? Its a issue for BSNL dataone users,they get frustrated ,some of them stop using internet for the time.But it might not the issue from BSNL end,it may be from your end also. ADSL light on-off problem may be from your end.
So here I have shown one block diagram of your connection of phone.

Here you can see line coming from BSNL exchange is going to your main phone and then its going to your internet modem.In such connection whenever there is change in phone 1 condition the ADSL light will be gone.So your internet connection will be lost.You can see how serially data is fed to Phone 1 then Phone 1 to Dataone modem.
Solution to this problem is making your connection like below.

In above block diagram you can see phone line from BSNL exchange is going to internet modem first.Then in modem there is output port for phone line.From there line is going to your main phone.So now whatever condition of Phone 1 changes ADSL signals are already has been filtered by your internet modem.So your internet connection will not disconnect.
If you want to use more than one phone make your connections according to below block diagram.
In this block diagram you can see after phone line is taken out from Internet modem there is parallel connection of all phones.So it won’t affect any phone or internet connection.
You can make such connection by contacting BSNL or on your own.
May 21, 2009 at 03:06:41
I have BSNL broadband 500 plan, with MT841 router. I am facing serious connectivity problems. Whenever a call comes it disconnects periodically.
How can you take out a wire from router and connect it to phone.
Originally, the telephone wire comes to my home, and then it goes into a splitter. the splitter gives two wires, out of which one goes to router and another goes to phone. where is the probability to connect phone after router? Don’t you use a splitter?
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May 21, 2009 at 20:23:44
here use of splitter is understood…in diagram where I have shown phone line is going to modem that means its going to splitter then one wire to modem and another to phone.
Your solution is same. Main line–>splitter–>1 to modem,1 to phone.Make 2 parallel connection in the line coming out of splitter for phone..as shown in diagram..and connect phone1 and phone2
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Aug 20, 2009 at 18:59:02
can u guide me why my skype on phone asks dat data connection needs permission… i m unable to use skype on phone ..
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Aug 23, 2009 at 20:45:44
Some phone restricts application to use extra features i.e. GPRS, data write read. It’s part of security of phone. So you can set always allow application to use data connection if you can, else choose Yes Allow when it asks it.
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Jun 15, 2011 at 11:50:56
Very informative, thanks. I have a parallel line in the hall while the phone line-splitter-modem + phone setup is there in an inner room where I work from home. Should I get a new splitter put up in the hall as well?
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KP Reply:
June 15th, 2011 at 2:51 pm
you need a splitter where you need ADSL signals. Remember no phone should be there before use of ADSL. If a phone is there split and separate ADSL signal.
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