Section 2 of 4
Four last miles
Four technologies reach American homes, and three of them were designed for something else first. What arrives at a given door depends less on what is technically possible than on what the operator already has in the ground outside it.
- Cable was built to send you television, and it never quite forgaveDOCSIS inherited a spectrum plan designed for downstream broadcast, which is why upstream stayed narrow for so long.
- AT&T stopped selling DSL to new customers in October 2020Copper is being retired unevenly, and what replaces it depends entirely on what the operator already has in the ground.
- What GPON actually splitsOne fibre from the exchange is divided passively between dozens of homes, which is why the shape of the network is a tree.
- Fixed wireless, and the orbitLow-earth-orbit satellite trades latency and capacity for reach, and reach is the problem it was built for.
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