[munk-a]

In most areas taxi-companies use a zone-based system where cars will flag what zone they're in (rarely automatically using GPS and more often via button presses) this is an effort by the cab company to keep their vacant vehicles well distributed to keep a high response rate and increase customer turnover.

It also happens to have the side benefit that an operator watching the flagged zones would be able to see this kind of an issue happening in advance and maybe check into why every cab is suddenly bee-lining it to zone 3.

[wildzzz]

But there should still be some override that would allow for a bunch of taxis to converge at one spot. Say a sporting event just got out, there's going to be a lot of people looking to catch a ride home. If you don't want all of those customers finding another ride, the system should have no problem dispatching drivers from other zones to pickup. Having a bunch of fares popup at the same location shouldn't be a major concern and it sounds like there were no safeguards preventing every driver from being dispatched. Without just adding a limit, like no more than 50% of taxis can be dispatched to a single zone, I'm not really sure how you could prevent this from happening again. I don't know exactly how the hack happened but if someone was just able to manually spam the dispatch queue directly, the only thing you could do going forward would be to place an automated check on every addition to the queue that it's from a real user with a valid credit card and that no other requests from that user exist in the queue.

[hinkley]

It’s a distributed system right? How do you prevent saturation of a single service?

Backpressure.

Add artificial delays to the queuing time, increasing for each taxi.

[lstodd]

Maybe that was the case 10 years ago. Or 15.

Nowadays it's all automatic, there are no predefined zones - only past statistics and about zero operators.

edit: srsly, that's what Uber is all about. and YTaxi is one of Moscow Ubers.

[munk-a]

My comment is about how Royal City Taxi, Yellow Cab Vancouver and Benways in Burlington work - I have never been an Uber driver or involved with the company and can't comment on how they manage drivers.

Also, you're saying my comment is out of date but this out of date system effectively solves the issue that just occurred with YandexTaxi - so maybe if you're working on a more up-to-date system you should borrow from the out of date tactics.