Hello and pls excuse my lask of knowledge in this subject.
For the UK is the general deployment of VoIP connectivity to the PSTN via ISDN2's and ISDN30's?
If so generally what interface card is required for the router for this, channelised e1 ?
IF it's an E1 you would need a RJ-48 Multiflex Trunk - E1
And the card would be:
This depends on the size of the implementation,
BRI supports two lines and BT can supply these with DDI numbers also they can supply bundles of BRI's with a common number so if you need 6 lines for example with DDI get 3 x BRI,
Next step up is PRI with 30 channels
BT can provide this with just 15 channels active to save some money.
Hope that helps