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"Whole new system" means basically putting Wifi AP's in the station, and on the trains and using WiFi localization technology that has been around for ages. Mos

"Whole new system" means basically putting Wifi AP's in the station, and on the trains and using WiFi localization technology that has been around for ages. Most of the money in that quote comes from the 20 year service plan (read: paying a few techs making $30-40/hr to be on call for 20 years). Should it really cost that much? Probably not.

danudey 2y ago
Well, "basically putting Wifi APs in the station and on the trains" isn't really what you want for a billion-dollar organization that handles 140 million rides a year. You need redundancy, upgraded communications paths, you need it to handle interference, you need it to work above and below ground, you need it to be secured. The 20-year service plan needs to include replacing hardware that fails (instead of just saying "sorry we don't make that anymore"); it needs to include security updates, expansions, it needs to include monitoring, it needs to include people knowing how the system works and what it does for 20 years (and not just having people retire and taking knowledge with them). It includes training, it includes escalation and SLAs, it includes the software (which will likely need to be customized for SF MUNI's specific needs), bug fixes, hardware support. It needs to support whatever OS they're running 18 years from now instead of just saying "Run Windows 10 on your clients until 2034 when it's 20 years old and you have to pay Microsoft for extended support". It boggles the mind that people on HN of all places look at short-form newspaper articles summarizing complex systems they don't understand and then post the most uninformed, reductionist armchair takes imaginable.
ThePowerOfFuet 2y ago
With CBTC, the localization is not done using Wi-Fi; balises and odometry tell the train exactly where it is, and it tells the system that via Wi-Fi or whatever other radio link it has.

danudey 2y ago

Well, "basically putting Wifi APs in the station and on the trains" isn't really what you want for a billion-dollar organization that handles 140 million rides a year. You need redundancy, upgraded communications paths, you need it to handle interference, you need it to work above and below ground, you need it to be secured. The 20-year service plan needs to include replacing hardware that fails (instead of just saying "sorry we don't make that anymore"); it needs to include security updates, expansions, it needs to include monitoring, it needs to include people knowing how the system works and what it does for 20 years (and not just having people retire and taking knowledge with them). It includes training, it includes escalation and SLAs, it includes the software (which will likely need to be customized for SF MUNI's specific needs), bug fixes, hardware support. It needs to support whatever OS they're running 18 years from now instead of just saying "Run Windows 10 on your clients until 2034 when it's 20 years old and you have to pay Microsoft for extended support". It boggles the mind that people on HN of all places look at short-form newspaper articles summarizing complex systems they don't understand and then post the most uninformed, reductionist armchair takes imaginable.

ThePowerOfFuet 2y ago

With CBTC, the localization is not done using Wi-Fi; balises and odometry tell the train exactly where it is, and it tells the system that via Wi-Fi or whatever other radio link it has.