• Nowadays most modern telephone systems have an extra way of connecting to the outside world. This is generally known as a SIP Trunk. This works over the internet protocol (IP) and tends to work in the same way as traditional ISDN 30 (2) services. Features and facilities such as caller line ID (for incoming calls) and outgoing presentation (CLOP, for outgoing calls) are typically charged as an extra service with service providers like BT. However, at NTA, these functions are part of our base feature set. Direct dial numbers can be added to any amount of SIP trunk channels. The difference between SIP trunking and ISDN 30 (2) services is that the boundaries around how many number ranges (max 5 with BT including single number DDi range) or geographic locations have been removed. As the numbers are delivered via our network, this allows us to cherry pick the number range regardless if it is a new number range that we have allocated, or a number range which has been ported in. We still have the capability to select a number and perhaps use it as a fax 2 email service or even an online conference room number.Direct dial numbers can be added to any amount of SIP trunk channels. The difference between SIP trunking and ISDN services is that the boundaries around how many number ranges (max 5 with BT) or geographic locations have been removed. As the numbers are delivered via our network, this allows us to cherry pick the number range regardless if it is a new number range we have allocated or a number range which has been ported in. We still have the capability to select a number and perhaps use it as a fax 2 email service or even an online conference room number.
  • SIP products powered by BT Wholesale and our business partner Adept PLC

    The price savings compared to ISDN30 are huge and the % savings grow as the number of channels increases …

    ISDN30 at BT standard rates SIP at AdEPT rates
    Length of contract 12 months 12 months
    No. of channels 8 8
    Price per channel £16.90 £3.75
    Total cost of channels £135.20 £30.00
    PSTN line not needed £13.25
    ADSL optimised for SIP not needed £21.99
    TOTAL MONTHLY COST £135.20 £65.24

    SAVING

    52%