Orange proudly announced they were first to market with a dual-mode 3G UMTS/WiFi phone last week. Available immediately in France, the service will be rolled out to Poland, Spain and UK later this year. Is this just another dual mode cellular/WiFi phone - or does it incorporate the technical changes within the network infrastructure which improve data throughput, latency and add a couple of extra services?

The standards were updated last year to allow 3G UMA phones when operating over WiFi to connect through the 3G Iu interface into the operator's core network (MSC voice switch and GSN data switch), rather than the 2G GSM equivalent called A and Gb respectively. This ensures that 3G only services, such as video calling can be delivered via WiFi (although I question how many people actually use this feature). Data performance and latency should be somewhat improved, because the Iu interface stripped out some of the unnecessary protocol layers and overhead present in 2G interface.

But I've learnt from industry sources that Orange's 3G UMA service isn't a full 3G service when operating in the WiFi mode - they haven't upgraded their network to use the Iu interface for UMA yet. All UMA WiFi traffic still goes via the old 2G A/Gb interfaces. The value of this product launch is simply a couple of new phone models (including a new UMA manufacturer), which incorporate 2G/3G cellular technology as so many other phones do these days. Therefore, the full benefits above of better data performance and 3G services on WiFi aren't available.

Data throughput rates of 1Mbit/s are being achieved over WiFi, which is thought to be adequate for small handset data uses.

The earlier GSM/GPRS specifications were really designed to handle data rates in the region of a few hundred kilobits, say 300kb/s maximum. That's not much use if your WiFi can handle 11 or even 54Mbit/s.

Orange have made it very clear in the past that they see little difference in the proposition between Dual Mode UMA/WiFi and Femtocells. We've previously reported their views on UMA versus femtocells and tabulated some of the tradeoffs between the two technologies.

I've been trying to work out exactly what you get, and at what price. The folks in the Orange PR department were quite helpful and responsive, but I'm disappointed at the lack of practical information on the graphically rich website - sometimes the benefits need to be spelt out very clearly such as the fact you will need a suitable handset, and what services you do and don't get in each mode.

What I've heard from industry sources is that Orange haven't updated their UMA equipment with the new Iu interface as yet. Instead, they're still routing the traffic through the existing 2G interface when operating in WiFi mode. This so called 3G UMA service therefore doesn't provide the benefits of the Iu (the more efficient and lower latency 3G data performance, new 3G services such as video calling etc.). The benefit is simply that your UMA phone can also operate in 3G cellular mode when out of the house.

The deal from Orange is that you must buy their fixed DSL broadband service. You can optionally buy their "Livebox" hub, which includes VoIP, Digital TV and WiFi or use a more basic WiFi access point. When away from home, you use the standard cellular mobile phone service (on 2G or 3G as available). On returning home, calls are switched to use WiFi. You can't use WiFi UMA service on the phone when away from home (except possibly if you are visiting a friend who also has Orange broadband and allows you to access their WiFi hub).

The same WiFi hub can support both 2G and 3G UMA phones simultaneously - its really just a dumb router in this case. Its quite possible that some household members may have older models and wouldn't want to replace them - especially when the choice of 3G UMA handsets is so limited at this stage.

It appears there is no extra charge for having or using the "Unique" WiFi service at home. Call minutes when on WiFi are presumably charged at domestic rates rather than coming out of your plan minutes. These are free at off-peak times of day and generally very competitively priced otherwise.

For voice handset and smartphone users, this competes strongly with the standard femtocell proposition. The primary disadvantages will be the extremely limited handset choice today (which presumably will continue to improve over time), and my unsubstantiated assessment that battery life is likely to be worse than a good 3G cellular short range signal.

Security for both UMA and 3G femtocells is excellent - all transmissions are automatically encrypted over the air. This is much better than many laptop WiFi connections at home, where encryption is not turned on (or even if WEP is enabled) and the transmissions can be easily monitored and intercepted.

Dual Mode WiFi continues to give the basic femtocell commercial propositions a good run for their money. Some will see this as breaking the ground for the seamless femtocell launches as they roll out in the coming 12 months or so. It puts the pressure on the femtocell industry to get to market quickly.