BT have announced they will be switching off their PSTN and ISDN networks. This article will explain what that means, and how you can prepare for these changes.
The Public Switched Telephone Network (PSTN) are landline telephone systems that you have in your home. When making calls via PSTN, analogue voice data flows over circuit-switched copper phone lines that are owned and operated by BT. This is a historic technology, built upon the original 19th century systems used for the very first public phone networks.
PSTN cables are the main carrier for internet activity across the world. Asymmetric Digital Subscriber Line (ADSL) and fibre-to-the-cabinet (FTTC) are both types of broadband that operate on PSTN copper lines. BT have not suggested that they will be stopping broadband travelling along these lines, they will just be ending analogue voice communication.
Integrated Services Digital Network (ISDN) was introduced in the 80s and allowed digital transmission of voice, video and other services simultaneously. ISDN uses the traditional PSTN network to perform this, but it offers both voice and data services to be delivered simultaneously. ISDN was well-suited to businesses, because it could support video-conferencing systems without interfering with an analogue phone line.
PSTN and ISDN are outdated technology, they are no longer the best option and hamper internet connections. Maintaining ‘legacy’ networks is also very expensive for BT.
Instead, IP-only lines can cover all services (voice, data, video, and broadcasting), meaning that BT only has to maintain one network. The recent investment and nationwide roll out of superfast fibre internet and new ethernet products provide a substantial improvement over PSTN and ISDN networks.
You have a few options to choose from before these changes take place:
Session Initiation Protocol (SIP) trunking will replace ISDN lines by default. With SIP trunking businesses need an internet connection and a phone system.
Voice over Internet Protocol (VoIP) allows you to make and receive phone calls through your internet connection. VoIP has been around since the mid-nineties and has proven to be reliable.
Cloud telephony is a managed service that enables your business flexibility as it stores your phone system in a managed cloud. This means less equipment, hardware, and maintenance costs.
– It’s quicker to have a new line put in
– You need fewer physical lines, meaning cheaper line rental
– It’s extremely flexible and scalable
– You can have a number for any region or country
– You can use your phone number anywhere you have an internet connection
The biggest difference between traditional ISDN and SIP networks for business owners is the cost. Communications between SIP users can be completely free, regardless of distance. This is because VoIP starts with a fixed cost for a phone number and extensions on a provider’s network (referred to as a SIP trunk). Unlike traditional phone systems where you are paying multiple times to be connected, you only pay for call termination charges with VoIP.