Need some advice


We are a UK hosting company and we are looking to setup an Asterisk IPPBX to service our clients providing them with “business” telephone numbers.

I’m fine with everything else, from hardware/servers/configuration - but seem to be given mis-information on the options for connecting the system to the telephone network.

Basically, I need to be able to offer our clients a selection of geographic numbers as well as 08xxx numbers. I have spoken to BT whom have said this isn’t possible via ISDN as you can only affix the geographic number of the location of the installation.

Therefore they have gone down a long elaborate route with BT One Voice product. Which is basically a SIP truck over a MPLS line into BT Core.

Just wondering what others are using and would recommend for connectivity to the telephone network from a Asterisk box which would allow multiple geographics as well as 08xxx numbers.



You could use a did provider, is one of them.

Going that route means you dont have to use BT, but depending on the numbers, BT might be the better option.

Just have to do some calculations.


Here’s another:

I prefer the terms SIP provider or ITSP (Internet Telephony Service Provider). People who call themselves DID providers often don’t provide DIDs but rather pass on a single number from a DID that trunk that they have, i.e. they don’t allocate a range of numbers and forward all or part of the dialed number to you.

If you used this terminology for simple analogue lines you would have to call the telephone company a DID provider, even for simple domestic lines.


Thanks for the replies, the numbers are large enough 6400 users/ddi, 1200 channels, 2mil minutes monthly is our estimated growth. Not really overly keen going through a third party prefer a direct purchase.

Its really just trying to understand what product or infrastructure everyone else is using? If they are offering multi-location geographic numbers.

There is only one person on this forum who might have experience of such large systems in the UK market, and I haven’t noticed them posting recently.

I think you are basically in the blue chip business telecoms market, and there may not be many players other than BT and NTL/Telewest.

My feeling is you need consultancy, but I suspect most the consultants on the Biz and Jobs forum will be providing consultancy to your customers. You want to become an ITSP.

Hello can you tell how can i forward calls from specific extension to the cell phone ? thanks

How about not stealing a post…

Then take a look at

and because Im in a good mood…

exten => 1234,1,NoOp(Forward extension 1234 to mobile)
same => n,Dial(SIP/“mobilenumber”@provider)
same => n,Hangup()

Yes, old school, still use the hangup…

Hi David,

Thanks for your reply, indeed technically we are fine with all other elements of the infrastructure.
It is purely the connectivity to the public network which we are now unsure on.

I had assumed we could connect MIXED-GEOGRAPHIC numbers to a standard ISDN channel, making the setup relatively easy and nothing beyond what we use internally. However BT have introduced SIP trucks via an MPLS which I want to ensure this is the “recommended” manner of achieving connectivity and don’t venture down the road of a product which isn’t suitable as the implementation fees are reasonable costly.