GPS traffic messaging FAQ

Traffic messaging for sat nav devices is now available for residents along Australia's eastern seaboard. But what is it? What does it do? Which devices have it? And is it any good?

What is it?
It sounds a lot like a service that sends you SMS updates about traffic conditions in your city but, thankfully, it's neither that limited nor that annoying. Instead it allows GPS units equipped with the necessary hardware and a traffic subscription — whether it's an in-dash or portable device — to receive traffic information.

What can it do?
A traffic-enabled GPS unit can either warn you of traffic incidents along your current route, automatically re-route around severe traffic delays, or both. You can also use your traffic-enabled GPS device to look up jams, road works, special events and so forth before heading off on your journey.

What type of incidents can it warn me about?
Traffic accidents, general congestion, scheduled road works, and special events, such as sporting events, concerts, street festivals or anything involving road closures.

How much is a traffic subscription?
At the time of writing (November 2008), if you buy a portable GPS with bundled traffic messaging, it will come with a lifetime subscription to Suna's traffic messaging services. By the by, that's the lifetime of your GPS device, not you. This differs significantly from some overseas countries, such as the US, where traffic services incur an annual fee.

Where is it available?
Currently Suna's traffic messaging network covers Greater Sydney, Melbourne (including Geelong, Mornington and all around Port Philip Bay) and Brisbane (as well as South East Queensland, as far north as Noosa Heads and down south to Tweed Heads).

CNET Australia understands that sometime in 2009 Suna will be rolling out TMC services in Perth, Adelaide and Canberra.

For more information on the coverage area check out Suna's website.

Which portable GPS units have traffic built-in?
The major brands — TomTom, Mio, Navman and Garmin — currently offer a number of GPS units with traffic messaging hardware and a Suna subscription out of the box. These companies also offer hardware and subscription upgrade bundles for selected devices that don't come standard with traffic messaging.

Also check out our round-up of the best portable GPS units with built-in traffic messaging, as well as Suna's website for a slightly more exhaustive list of traffic-enabled GPS devices.

I've got an older portable GPS with traffic messaging, but it doesn't work...
Prior to mid-2008, when traffic services were only available in Melbourne, only a few portable GPS devices were sold with bundled traffic messaging hardware, such as Mio's DigiWalker C720t and Navman's S90i. These navigators require the purchase of a lifetime subscription to Suna's service — available for the Mio here and here for the Navman. Purchasing this AU$129 subscription is all that's required for Melbourne residents.

If you live in Sydney or Brisbane though, you will also need to purchase the 2008 (or later) version of the Whereis maps from either Mio or Navman. This is because the 2007 maps shipped with these devices do not contain the data attributes, in both Sydney and Brisbane, required for traffic messaging to work.

Can I upgrade my existing GPS to make it traffic enabled?
For many portable navigators sold in 2007 and 2008 the answer is probably yes. It is best to check out the Australian website for your GPS device to see if this is possible. If it is, you will need to purchase a traffic messaging cradle, which should come with a lifetime Suna subscription thrown in. Most manufacturers' cradles cost about AU$150. Also, if you live in either Sydney or Brisbane and aren't already using a 2008 map, you will need to purchase one from your GPS maker.

Which cars have traffic built-in?
So far only Ford's Falcon range has a GPS system equipped with both traffic messaging hardware and the service subscription. With all GPS-equipped Falcons sold from August 2008 onwards equipped with the necessary kit. According to company representatives, upgrading and subscribing sat nav-equipped FG Falcons sold before 1 August is a fairly simple task for most dealers.

Suna have informed us that it is working with car makers to make its services available in more new cars.

But my car's sat nav system says it can do traffic messaging, yet it doesn't work ...
Many cars equipped with GPS, especially those from European brands, have traffic messaging hardware built-in but aren't armed with a subscription to Suna's service. To our understanding, upgrading these cars to work with Suna's system is not yet possible. CNET Australia will keep you abreast of any developments.

How does it work?
Suna's service broadcasts digital, encrypted TMC (Traffic Message Channel) data containing traffic information. These messages are piggybacked onto an existing FM radio station's signal — for example, Mix 106.5 in Sydney and Gold FM in Melbourne — and received by GPS devices equipped with a TMC receiver and Suna subscription.

How does Suna collect traffic information?
Traffic information is collated at the company's Melbourne headquarters before being fed out across its TMC networks in Sydney, Melbourne and Brisbane. Sources include roadside assistance providers, emergency management services, road work registries, special event organisers and tow truck dispatch services. However, the major component in Suna's traffic information jigsaw are the state road authorities, like the RTA in NSW and VicRoads in Victoria. They not only provide Suna with access to their traffic centres, but with live data from the sensor pads built into many roads which regulate traffic light timing. This data is then fed into Suna's traffic modelling software.

Is it any good?
In our experience the traffic messaging system, in Sydney at least, works well most of the time. Significant delays on major roads and motorways are usually picked up in a timely fashion, however there were several instances when we found ourselves stuck in traffic that either had yet to be picked up by the system or wasn't deemed to be significant by the powers that be.

We've also encountered the reverse situation where we've driven through seemingly phantom traffic delays. In some instances this was, presumably, because a delay had cleared yet the event had yet to disappear off the system. In other cases though, this was because scheduled events, such as road works, had yet to start. Also delays on some of our favourite peak hour rat runs were rarely, if ever, covered by the system. This is because Suna's monitoring system draws heavily upon cameras used by state road agencies, which generally don't cover minor roads and streets.