[lcuff]

While the author is right about his particular case, it doesn't generalize to every case. A few years back I was involved in a startup that was writing software to optimize climate control systems in very large buildings. Unfortunately such buildings are usually decades old, and have antique internal networks. In many buildings, it was impossible to get the data out. (Network bandwidth problems: We wanted data from thousands of sensors every 5 minutes). They had twisted pair wiring. I'd say we were two to three decades early to market. We needed buildings to have their internal networks upgraded, and yet they had no immediate reason to do so.

[rwallace]

Intuitively I would expect that to work even with twisted-pair; each sensor needs to transmit for maybe a millisecond every 300 seconds, which would allow for 150,000 sensors while still using only half the available bandwidth. What am I missing?