While everything at VON is, of course, billed as breakthrough, disruptive, playing field-changing technology, one of the most potentially disruptive new developments made its debut before the show, on Monday at San Jose-based HelloSoft’s open house.

When Alexander Graham Bell uttered those fateful words, “Mr. Watson, come here I want you” I’m sure that no one was reporting about the voice quality.

So when I experienced a seamless WiFi-cellular call handoff yesterday, I wasn’t focused on the details so much as the fact that this was actually working. With people calling seamless handoff the “holy grail” of convergence, well, I was excited to see it work.

I’m pleased to report that unlike much new technology, it didn’t just work the first time. It pretty much…worked.

While the handoff was audible, sound quality was acceptable. The phone has a single phone number — HelloSoft’s other dual mode phones have separate numbers for the WiFi and cellular networks. The handset shows network strength for both networks as well as highlighting what network is currently carrying the call.

While seamless handoff isn’t going to change the world as profoundly as Bell’s invention, it has the potential to change mobile telephony pretty significantly.

Of course, some question if voice WiFi — even in its dual-mode incarnation — the tree to be barking up? Especially as at least one carrier recently dropped its dual mode phone.

There’s plenty of opportunity, says Ron Victor, HelloSoft GM, Marketing and Business Development, although he does say that the technology-focused business model for WiFi phones has been flawed from the get-go.

“People don’t care what infrastructure you’re on,” he explains. “They want good voice quality at a very low price. When was the last time you said, ‘Is my call going through an HSDPA network?’ The assumption that people are going to jump to WiFi was fundamentally wrong. What’s the value proposition?”

The Skype-only handset illustrates a business model that does make sense, Victor says. “Why do people use Skype? Because it’s free. The Skype handset is more convenient, more flexible, more grandma-centric. You have a value proposition.”

“In voice over WiFi, the only way you’re going to entice me to use it, is that you’re going to slash my phone bill,” he continues. “But if you drop it to $25 a month, well Vonage has done that already. But if you tell me you’re going to drop my phone bill to $5 a month, then you’ve got my interest.”

One of the value propositions Victor sees for a dual mode phone is the potential to save businesses sacks of money on corporate cell phone bills. “Companies are already paying for cell phones for their employees,” he explains. “There are huge savings if you can move mobile phone calls to the enterprise network. Industrial applications — that’s where voice over WiFi is going to happen.”

Or as someone else I encountered at VON, Jeff White of Cognio put it, “The killer app for wireless is VoIP. The killer app for VoIP is wireless.”

HelloSoft is showing its line of dual mode phones at VON. The company is also running shuttle buses to its open house down the road where visitors can try out the seamless handoff for themselves.

VoIP software company HelloSoft is holding a special press shindig next Monday — a pre-VON warm up. The San Jose-based startup is inviting members of the fourth estate to shmooze with HelloSoft execs and take the company’s seamless cell-WiFi handoff technology for a spin.

Moving a call seamlessly between cell and VoIP networks is certainly sexy. But before you can move the call between the networks, you first need the capability to make a VoIP call over a WiFi network reliably.

So I called up Meru Networks, the Sunnyvale networking company that specializes in wireless LANs for organizations like college campuses, hospitals and corporate campuses, to ask some experts what it takes to assure that we’ll be able to use HelloSoft’s technology when it hits retailer shelves.

Although Meru isn’t in the metro WiFi business, the challenge is nonetheless the same.

“What customers want is guaranteed application delivery on a secure network that supports high quality voice, hi-speed data, streaming video,” says Michael Tennefoss, Meru Networks VP of Marketing. “If they have it on a wired connection, they want it on the wireless network.”

But when you peel back the technology onion, delivering that quality of service isn’t so simple.

“The first issue is establishing and maintaining the connection,” Tennefoss says. “When you’re walking around on a WiFi phone you have a problem you don’t have at home when you’re in close proximity to your wireless router. You have the problem of how the call moves across access points.”

There are two ways to do this. One method is where the device — telephone, laptop — makes the hand-off decision between access points based on signal strength. This is used in many legacy wireless LANs.

The other method, used in the cell phone world, makes the handoff decision centrally. This is the method that Meru favors.

When the traffic is voice, Tennefoss says, “You have to think of a client/server architecture. You can’t leave it us to the device [to determine the access point] because it affects others. To make it work you need to know what applications they’re running. You need a parent to make sure they play well together.”

Then you can balance the load based on the application. For example, email doesn’t need as much radio power as a voice call. “You have an intelligent handoff based on what the user is doing,” Tennefoss explains.

Meru has no small amount of experience delivering mobile VoIP in some challenging environments: hospitals (lots of metal), college campuses (indoor/outdoor environment), and corporate campuses.

One of the lessons of this experience is that existing wireless LANs can’t be relied on to deliver the next generation of application mobility, Tennefoss says. “The wireless infrastructure that may have been put in for email can’t accommodate these gadgets. Some can only handle four calls at a time. You can’t have that in a hospital.”

And as wireless becomes the de facto connection, it doesn’t take Nostradamus to predict that we won’t tolerate those limitations anywhere, opening more doors for the Merus of the world.

In what municipal wireless broadband provider 4G Metro is calling a national first, the company will deliver wireless Internet access and “entertainment” services to passengers riding Trinity Railway Express, a cooperative commuter service between downtown Dallas and Fort Worth, TX and the Dallas Fort Worth airport.

There’s no explicit statement about how this gets paid for, but the LCD screens providing “infotainment” that are part of the deal suggest one revenue stream. Also, the fact that Airpath Wireless’ RoamBoss will be used for provisioning, user authentication, e-commerce and billing suggests another.

So let’s add this up.

You pay your $9 for half an hour of connection while you ride to the airport. Then you pay another $9 to connect to whatever service is offered at the airport (chances are it’s not the same). When you get to your hotel you pay another $9 or $10 to connect in your room. On your return trip you get dinged for these charges again.

Pretty soon, whatever Sprint is charging for EV-DO is looking pretty good. Or, if we’re going to be nickeled-and-dimed, how about in real nickels and dimes instead of five and ten dollar bills? That I could live with.

For more details, you can read the press release.

Whenever the talk gets around to wireless applications and services, the question of the infrastructure to deliver all this whiz-bang stuff always seems to get glossed over.

It’s like Futurama (the 1939 version, not the 1999 cartoon). No one back then spent much thought on the underlying technology that was going to whiz us around town at light speed or make the kitchen obey our every wish. Likewise, the ubiquitous WiFi that’s going to deliver every imaginable service to mobile phones and laptops.

I’ve written several times about the problems of trying to connect in the mobile present — forget the future. Most recently, yesterday afternoon.

So I was interested today when I saw “The No-Hardware Wi-Fi Community” by Eric Griffith in WiFi Planet. Some people aren’t waiting for the second coming of the Internet.

They’ve started a grass roots movement to create WiFi communities by sharing their own networks. You let me use your network and I’ll let you use mine — the same way Skype users share their networks.

Now, my neighbor is already doing something like this. He doesn’t have any security on his network by choice. (No, I’m not going to give you the address). But these companies offer a way to limit use of your network to your particular WiFi community.

Spanish startup Whisher Technologies launched a beta version of its service yesterday. Whisher offers free downloadable software that lets you share your WiFi network with other Whisher users and use theirs.

The plug-in lets you control who has access to your network, but eliminates the need for all users to have the password or key. You can leave your network completely open to all other Whisher users, buddies only, or open only to you and specific individuals.

Another company promoting the same type of grass roots WiFi liberation is one year-old Fon — another Spanish company — which sells a customized router for $30.00 that lets users share their networks. If you don’t open your network to other members of the community (Fonsters?) you have to pay $3 a day to use the network — still a bargain compared to typical ISP day pass charges.

The fly in the ointment here is that sharing your WiFi network past the front door of your house may be illegal, according to a story by Marguerite Reardon at CNET News.

“We’ve taken steps as a company to inform our customers that passive or active theft of our services is illegal, and people who violate these agreements can be prosecuted on a criminal and civil basis,” a Time Warner spokeswoman is quoted saying in Reardon’s story.

Isn’t that always the way with big companies? They’re all for competition and free markets until someone acts on those free market ideas and starts competing. Then they start acting like schoolyard bullies.

It makes me want to put up a sign on my front door: Steal this network.

Mobile VoIP is a hit with consumers according to the “Mobile and WiFi Phones and Subscribers” report released today by the Campbell CA-based telecom analyst firm Infonetics Research.

While mobile phone sales worldwide were up a healthy 13 percent in 2006, the interesting number is a 327 percent growth in WiFi phone sales during the same period.

Still not impressed? Consider what Infonetices predicts for the rest of the decade: A compound annual growth rate close to 200 percent for cellular/WiFi dual mode phones.

Consumers are choosing these two to one over single-mode WiFi equipment. In 2006 71 percent of WiFi phone revenue came from dual-mode handsets while single mode WiFi made up only 29 percent of the total.

The report is certainly good news for makes of dual mode handsets; a rapidly growing field that includes established mobile phone players like Nokia as well as newcomers like San Jose, CA-based Hellosoft.

The numbers reflect user impatience with juggling multiple devices, according to Infonetics.

“Users are demanding single number/single device services, and operators like T-Mobile announced converged services based on Unlicensed Mobile Access (UMA) in 2006,” said directing analyst for wireless at Infonetics Research Richard Webb in today’s press release. “UMA is a good example of early fixed-mobile convergence (FMC), prior to the eventual shift to IMS in the long-term.”

“More operators are transforming into integrated multimedia service providers, creating converged mobile, wireless LAN, and VoIP solutions that support voice and data services across enterprise, public, and home networks,” Webb continued. “The appeal of such converged services is driving WiFi phone adoption, especially in dual-mode WiFi/ cellular handsets.”

Other highlights of the study include:

• 2G/2.5G GSM handsets made up 49 perent of worldwide mobile phone revenue in 2006; the remainder was made up by 2G CDMA, W-CDMA, and CDMA2000 handset sales.

• Worldwide mobile subscribers are estimated at 2.5 billion in 2006 (up 26 percent from 2005), and are forecast to grow 42% to 3.6 billion in 2010.

• Cisco leads in single-mode WiFi handset revenue market share in 2006, followed by SpectraLink.

• Samsung leads in dual-mode WiFi/cellular handset revenue market share, followed by Nokia.

• North America leads in worldwide revenue for single-mode WiFi phones, and Asia Pacific leads in revenue for dual-mode WiFi/cellular phones.