BT Wholesale has announced that from 2020 you will no longer be able to purchase integrated services digital network (ISDN) and public switched telephone network (PSTN) circuits as it targets a 2025 switch off date.
Questions are naturally being asked. Will BT really flick the switch in 2025? What needs to be in place before that can happen, and what are the options for those currently on ISDN/PSTN circuits?
Last year, BT boldly announced its intention to switch off its PSTN and ISDN networks by 2025. This was a smart move. In a world that is fast embracing IP as the standard protocol for all communications services, it was important for BT to declare its intentions to remove the legacy from its network, while giving customers a whole decade to make the switch (if they haven’t done so already).
What does this announcement really mean?
Let’s start by looking at what PSTN and ISDN really are. PSTN is the same phone line most people have at home, whereby analogue voice data flows over circuit-switched copper phone lines. While it may have evolved over the years, PSTN is a very, very old technology, operating on the same fundamental principles as the very first public phone networks of the late 19thCentury. It is worth noting that PSTN does not just power voice, as asymmetric digital subscriber line (ADSL) and fibre-to-the-cabinet (FTTC) both operate on it. As of yet BT have not suggested any replacement technology for these, so one can assume that BT’s planned obsolescence of PSTN applies to voice only in this instance.
ISDN, by contrast, is a spritely young thing from the late 1980s. ISDN allows both voice and data services to be delivered over digital lines simultaneously. When it launched, ISDN was well-suited to businesses, as it could support early video-conferencing systems at the same time as an analogue phone line. For a time, it could also offer the fastest internet access available (128 kbps). Naturally, since ISDN is no longer the place to go for video-conferencing or a fast internet connection, its USP has quickly been eroded.