The Public Switched Telephone Network (PSTN) that has provided telephony services for many decades is being retired across the world along with the copper wires that crisscross cities, towns and the countryside connecting homes and businesses.
PSTN services are being replaced by voice over IP (VoIP) services delivered over broadband connections which eventually will depend entirely on optical fibre rather than copper.
Some countries such as Germany, Norway and Sweden have already switched off their PSTN while others such as Denmark, New Zealand and the UK plan to end PSTN services at or before the end of this decade (the UK will end its PSTN services in 2027). Other countries such as the USA and Canada are transitioning to VoIP services but without an official deadline.
VoIP over fibre broadband has many advantages for service providers: PSTN equipment is old and so is becoming unreliable. Copper networks also require much more maintenance than those based on optical fibre. It is estimated that the recycling of redundant copper cables in the UK will result in a two billion pounds windfall over the next decade for the network’s owner. VoIP services over fibre can be provided with less equipment, physical space and sites than the PSTN allowing the selling off of redundant exchange buildings.
There are advantages to customers as well, particularly business users. VoIP services provide higher quality calls and greater flexibility with call rerouting facilities.
However, the transition to VoIP services does have to take into account that some existing attached equipment such as burglar and fire alarms rely on copper PSTN connections. Unlike a PSTN connection, VoIP over broadband stops working during a mains power failure (backup batteries may be provided but these have a limited power feed duration). This is especially a problem for customers in those rural areas where mobile coverage is poor and so may not be able to make an emergency call.
PTT’s online courses Introduction to Telephony and Voice over IP provide a detailed explanation of the features and operation of VoIP telephony for those responsible for the provision of VoIP services.