FM and XM traffic information are limited by their simplex distribution methods to major metro areas. Due to the simplex nature of the channel, there may be a bandwidth problem. Let’s assume that flow data is better than incident data. Let’s also assume that the goal is to provide all of the relevant and reliable data to each traffic-enabled GPS device (be it a traditional navigation device or a cell phone). With a simplex distribution channel, the data source has no way of filtering the data to reduce the necessary bandwidth, beyond just limiting the data to major arteries or decreasing the depth of the data. It must broadcast all the data it has that is relevant to its coverage area, and it must broadcast on some sort of cycle, limiting the update frequency for the end-user. The user might end up being in the middle of slow traffic before the GPS hears about it from the broadcast source. There is a trade-off between the breadth of the data (just freeways, freeways+major surface streets, or all surface streets), the depth of the data (just incident data or incidents+flow data) and the update interval.

With a duplex cell connection, the device has the ability to query the source, requesting only the relevant data and receiving the relevant data faster. Since irrelevant data is filtered out, there is room on the channel to include better information: more surface street data and traffic flow data wherever it’s available.

If you only need data for major arteries AND only need data for metro areas AND can tolerate delays of 15 minutes AND can tolerate only having incident data in some areas, then there is no distinction between a traffic antenna and cell data traffic.

Personally, I’m looking forward to the 1690 and similar devices.

I don’t think the upload capability of a GPS will help in any material way. GPSs aren’t ubiquitous enough to provide meaningful probe data to traffic vendors. The only usable scale is in probes from a cellco company like Airsage/Verizon.

Once this cell-probe info is translated into traffic data, it can be broadcast via any medium: antenna, cell data, etc.

As traffic probes move to using the gps in consumer cell phones traffic reporting accuracy will increase exponentially.

Inrix has long been the leader in fleet probes citing about 900,000 of those probes. Of those some percentage travels at night to avoid traffic, some percentage is rarely on secondary roads, some percentage is dropping off a load for quite some time and not feeding back and some percentage of fleet vehicle probes are good only for historical data since the data is delayed. At the end of the day they never had 900,000 probes available and at any one time much less than 900,000.

Mistelle is po’d because the competition, here Google, is giving away what he wants to charge for making Inrix less valuable and maybe in trouble. At the other side of him is Navteq Traffic with the huge resources of Nokiq about to eat Inrix for Lunch here and in Europe. The Darkhorse here is NIM which has 3 million gps probes and moved to use them by buying the back office ops of TrafficGauge. That could tip the probe count depending on who gets access to them.

The 740 is good at avoiding traffic jams I anticipate that the 1690 will be better but time will tell and these are really still first generation real time devices. Dash had a good concept but rather than focus on the core routing and traffic avoidance they made it the darling toy of the blogosphere and ended a commercial failure.

In the early days of online maps, there was a lack of trust in the route. In the early days of in-car GPS, there was the same problem. In both cases, the data has gotten better, and people are confident on relying on the provided route. We are in the early days of live traffic data. Google is now collecting live traffic data from cell phones. RIM has acquired Dash. Garmin’s 1690 is coming soon. Connected GPS devices will soon become ubiquitous, and people will start trusting the data.

I understand your concerns. When I use google maps, it’s not very good at routing around bad traffic. When I had a Dash, I’d frequently use my own route as a commuter. The Dash didn’t have a data quality problem. Where it had data it was quite good. The problems were in data quantity and poor algorithms. In both cases, it was nice to be able to visualize the data and pick my own route. I just don’t think that will be necessary in the near future (within the next 1-2 years).

On a navigation system, who cares how the current traffic compares to historical data?

If that was the case, then why do GPS devices show traffic data at all? If the GPS will pick the best route through traffic, then why do the roads need to be colorized? I think the answer is that people don’t completely trust the data. Speaking from the eyes of a commuter, they want to see the data but then make their own decisions. If a commuter has a navigation system with a traffic map that colorized based on comparing current to historical traffic they might not even create a route to where they are doing– they might just look at the map, make their own routing decision, and drive. I’m not saying people should make their own decisions as the little processor can do the math easier, but people generally don’t trust the traffic data and tend to want to make their own decision… correctly or not.

Admittedly, in the past, there were some problems with both the quantity and quality of data. I was a Dash owner, and frequently ignored its recommendations in the early days if I was commuting.

As data is increasingly collected directly from the users (connected GPS like the Garmin 1690, gps-enabled cell phones), both the quantity and quality of data will improve, and users will be able to trust their navigation systems to provide the fastest route.

The only situation where this is a significant problem is when using google maps for looking at traffic patterns but not doing any routing. Google maps already–in some cases–can predict the transit time “in traffic”. I would imagine that as their data gets better, you’ll see the option in google maps to automatically choose the fastest route in live traffic.