[Routing] Introducing "noise" when routing

[Jon Bright]

Gerald A wrote:
> 
> I might be missing something, but assume that there are N drivers with
> the same satnav system. Now, they get an update on traffic and are
> diverted to an alternate route. Without some fudge/noise factor,
> wouldn't you simply be moving the congestion to another route?
> (Assuming that N is a significant number of drivers, and they are
> fairly close together on the preliminary congested route).

Assuming they all start their journeys at the same time and are all at 
the same distance to the next exit or next "fork" to a different but 
near-optimal route, yes, you'll do that.  In real life, even if there 
are rush hours, people's journeys don't start at the same time, don't 
all come from the same start, don't all go to the same destination, 
don't happen at the same speed, in (or on) a vehicle with the same 
capabilities or in the same lane... real life has already added enough 
"noise" for you.

Plus, I think the danger of OSM-based navigation systems reaching the 
kind of market penetration where this becomes a problem at all is 
currently remote :-)

-- 
Jon Bright
Silicon Circus Ltd.
http://www.siliconcircus.com