Digital Voice is BT’s proprietary telephone service, it’s unfortunate that other ISP have chosen to use the same name for their own IP telephony, as it’s likely to become a generic term for all IP telephony when it’s not .
BT DV has nothing to do with Openreach, it’s not a wholesale product made available other ISPs but obviously other ISP could develop or purchase an off the shelf product that operates in a similar way , no doubt there will be a common set of standards for IP telephony , but obviously BTDV is integrated into the SH2 , hence the complaints from some that don’t want to use the SH2 but are a BT telephone customer.
If BT supply telephone ‘BTDV’ instruments , that state ‘ compatible with BT DV’ , they may work with other providers IP services, but it’s possible that some ‘BT’ features that are integrated into the handset , may not work with other vendors versions of IP telephony , if they don’t work in Vodafone DV ( for example ) that’s of no concern to BT .
