hi Linker,

I don't understand your question. what you said is a basic function
for an FXO gateway. please have a look at
http://www.telecomchinasourcing.com/...article&sid=17
.. the first diagram is as same as what you will deploy.

The authentication method could be many kind. in you case, I think the
voip provider need the BT line's phonenumber. you could just configure
it into your gateway. when the BT line recieve calls from PSTN, it can
start a voip calls with your BT line's number. The Shang308 can do it.
Is that what you want?

Hawk


Linker3000
> Hi,
>
> I have tons of landlines managed by Company 'A', who have 'taken them
> over' from BT and do Carrier Preselect etc. for us.
>
> I want to port one number to a VoIP provider - Company 'B'.
>
> B has sent me a form to authorise the porting - the form requires the BT
> account number for the line - which it doesn't have as far as *we* are
> concerned.
>
> I have spoken to 'Sales' at A and they say they will have to release the
> line back to BT and we *may* be locked into a 12 month contract with BT
> before we can port it out again!?
>
> I have spoken to a techie at A who has found the BT account number they
> have for the line as they have to still rent it from BT on our behalf.
>
> I am trying to bang A and B's heads together on this to arrange a direct
> port between them, but they seem to not have done this before (ie: port
> a number that is no longer with BT) - so does anyone hereabouts have
> experience of porting to a VoIP provider when then line's already with a
> non-BT service provider?
>
> I can see that the form could be filled in by the line's current
> 'keepers' (A), but is that likely to work - neither A nor B can give me
> a straight answer to that one rather than 'well we can give it a go and
> see what happens'.
>
> Thanks.