Digital Voice

[jac_95]

To be clear those that are not yet moved to VoIP and are still on the PSTN, local numbers are honored (i.e don't have to dial area code even if the number on the other end has has been moved to VoIP)

Those that have been moved to VoIP will have to dial area code on outgoing calls.

[licquorice]

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@jac_95 wrote:

@Anonymous 

That happens today on BT Digital Voice if you don't dial the area code it will say for you to dial again and include the area code.

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Hmm, how does DV determine the area code hasn't been dialled rather than insufficient digits? Or does it always assume insufficient digits equals area code not dialled. How long does it wait after the final digit to decide that no further digits are to be dialled and make the announcement.

[jac_95]

@licquorice hahahha you asking me how they've implemented it? I've not tried the different scenarios or know the technical implementation here but there are many ways you could do this, from regular expressions and using lookup services and validation API services to also introducing a delay between receiving the number being entered to then initiating the lookup and validation.

[Keith_Beddoe]

 API services to also introducing a delay between receiving the number being entered to then initiating the lookup and validation.

That reminds me of the old Strowger mechanical regenerators on a director system, where it stored all the dialled number until it could determine the correct routing, it then resent the digits. It was a mechanical marvel with push pins for memory. The pins often got stuck and the calls failed, so an electronic version was introduced.

That was a very long time ago, but part of my initial training.

[Bob1001]

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@Keith_Beddoewrote:

 API services to also introducing a delay between receiving the number being entered to then initiating the lookup and validation.

That reminds me of the old Strowger mechanical regenerators on a director system, where it stored all the dialled number until it could determine the correct routing, it then resent the digits. It was a mechanical marvel with push pins for memory. The pins often got stuck and the calls failed, so an electronic version was introduced.

That was a very long time ago, but part of my initial training.

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The hardest course I did at Stone, pins everywhere when the spring slipped.

[iniltous]

All ‘STD’ calls begin with a ‘0’ , so any ‘processor’  will within milliseconds respond accordingly if a call is attempted that isn’t valid ,in other words if you don’t start the call with a ‘0’.

AFAIK , only BTw support local area dialing so anyone calling the OP who isn’t a ‘BT’ customer ( so customers of Sky , Talk Talk etc ) will already dial the full number when they call the OP , and there are many areas where BT require the full number to be used anyway  ( my area is one ) this was introduced  way before the advent of Digital Voice ,  dialling the STD code isn't a hardship.

FWIW , it’s been 30-40 years since calls were routed on a ‘step by step’ basis , as each digit dialled the call progresses with that digit, even with tech that’s been around for 40 odd years , an enquiry  isn’t even made to the destination number until all the phone number digits have been entered , then in milliseconds the destination is interrogated, if the line is ‘free’ the destination line providers  ‘equipment’ starts to ring the called ‘line’ and the caller hears ‘ringtone’ but even this isn’t a connection  , it’s only if the destination actually answer , that a call path is setup between the caller and called party, it’s much more efficient than having equipment tied up with people listening to ringtone.

[Keith_Beddoe]

Also numbers beginning with 1 and 9 have to be accepted, plus country code prefixes and special service codes.

[iniltous]

Calling ‘International’ numbers still require the first digit to be a ‘0’ , but it’s a fair shout about emergency and customer service numbers , but the overwhelming majority of calls made , begin with a ‘O’ .

In my case ( not on  DV but an area that requires all calls to include the STD code even calls with the same local exchange area   ) , the AVR ‘ the number you have dialled has not been recognised, please check and try again ) is delivered after the first digit if it isn’t a ‘0’ ( digits 2 to 8 return the AVR ) , perhaps 1 or 9 may not do this until a second digit is entered .