Guides · 4 min read
The PSTN switch-off, explained
The copper phone network is being retired across Europe. Here is what that means for consumers, businesses and critical services.
By Elena Marsh · Infrastructure Editor
Fibre Networks
Fibre Networks
How optical fibre carries the world’s data — from access networks in the street to the backbones that span continents.
Last updated 14 Jun 2026
- Medium
- Glass
- light over silica fibre
- Last mile
- FTTP/FTTH
- fibre to the home
- Trend
- Copper retirement
- PSTN switch-off
Optical fibre is the physical foundation of the modern internet. By transmitting data as pulses of light through hair-thin strands of glass, fibre delivers vastly more capacity, lower latency and greater reliability than the copper networks it is replacing.
Access vs backbone
Networks are usefully split into the access layer — the “last mile” connecting homes and businesses — and the backbone, the high-capacity long-haul routes between cities and countries. The economics and engineering of each are very different.
The copper switch-off
Across Europe and Asia, incumbents are retiring legacy copper (PSTN) networks. This is one of the largest infrastructure transitions of the decade, with profound implications for consumers, businesses and emergency services.
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