File this one under “makes no sense”. While Openreach has been building trial networks for fibre-to-the-premises (FTTP) and fibre-to-the-cabinet (FTTC), it has also been overlaying copper on fibre access networks built back in the 1990s.
The legacy technology, called TPON (a term I hadn’t come across until today) was originally installed in outlying housing estates that were often a long way from the main telephone exchange.
TPON stands for Telecommunications Passive Optical Network, and was the first incarnation of PON developed by BT back in the 1980s to deliver 144 kpbs to 128 users from a single fibre. Quite simply, BT saved money by installing a single fibre to a TPON node rather than a separate copper line for each customer premises.
When ADSL started to really take off around 2004, customers served by TPON found they couldn’t get broadband service over their lines – TPON equipment being designed for voice calls only. As recently as October last year, BT was replacing TPON services by installing new copper lines.
Oh the irony. While TPON only supports voice calls and not broadband, Openreach currently doesn’t have a product to deliver voice over next-generation access at its FTTP sites.
Amazing! Never heard of this before, thanks for sharing.