Vendor lineage
Paradyne - the last miles of the analogue era
Squeezing usable data rates out of the copper that was already in the ground.
Paradyne built modems and data transmission equipment through the period when the access line was the constraint on everything. Its problem was the one the whole industry shared and few companies specialised in: the wire between a building and the network was already installed, could not be replaced economically, and was never designed for data.
That constraint outlived the analogue era entirely. Every subsequent generation of access technology - the DSL family most obviously - is the same engineering problem restated: extract more from existing copper because replacing it costs more than the service is worth.
It is a useful corrective to a timeline otherwise full of companies inventing new media. Most of the world's bandwidth problems have been solved on cable that was already there.