In this updated infographic, “ISDN is dead, long live SIP”, we explain the reasons behind the decline in ISDN use for business telephone line services and why SIP is the favoured alternative.
BT Wholesale has confirmed ISDN and PSTN voice services will no longer be available to purchase from September 2023. This is an issue that businesses cannot afford to ignore.
Four years may seem like a long time right now, but it will fly by, leaving any businesses who have not prepared for migration to SIP in a rather uncomfortable situation, especially as the long-term plan is to switch off all ISDN and PSTN voice services in December 2025.
If you are unsure what SIP is, please read our no-nonsense fact sheet on SIP to find out more.
Meanwhile, please see our infographic below: