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davidga
Beginner
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Message 1 of 4

Does old ISDN line affect my broadband speed?

Yesterday I was upgraded to BT Infinity.   BT stated "The minimum guaranteed speed you can expect from your broadband will be 32Mbps. "

So far, the best download speed I've achieved (with ethernet connection from my laptop to the HH6, with the latter plugged into the test socket in my BT Master socket) is about 26 Mps.  That drops to about 20 Mps when I use the external socket on the master.

Perhaps it's too early to expect the speed to have settled down...?

But it also occurs to me that there may be a problem with the rather peculiar wiring of my house: a former occupant had an ISDN line as well as an ordinary phone line.  Where the external BT wire (black, middle) from the telegraph pole reaches the house, it goes into a box on the fascia, and two wires come out of the box and enter the house: the black one (left) is the old ISDN line and the white one (right) goes to the current BT master socket. See picture:

Fascia box.jpg

 Another former occupant had the ISDN line de-activated, and both wires (black and white) are now used for extensions for my single phone number. (NB: there is no master socket on the black line.)

When I last had an Openreach engineer out, a couple of years ago, he said that there was no problem with this arrangement.  However, that was with the old copper (snail-speed) broadband. 

But could it be that there IS a problem now that I've upgraded to fibre?

Any suggestions most welcome!  (And apologies for the lengthy post...)

David

 

 

 

 

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Distinguished Sage
Distinguished Sage
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Message 2 of 4

Re: Does old ISDN line affect my broadband speed?

Yes, you have what is known as 'star wiring' and will affect your broadband speed. The cable to the extension should ideally be disconnected.

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davidga
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Message 3 of 4

Re: Does old ISDN line affect my broadband speed?

Thanks, licquorice!

David

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Distinguished Sage
Distinguished Sage
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Message 4 of 4

Re: Does old ISDN line affect my broadband speed?

the speeds quoted by BT are connection speeds not download speeds 



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