The cellular value chain collectively scoffed when voice over WLAN first hit the scene several years ago. Who on Earth was going to use battery-draining handsets for networks with a range of 100 meters when they had a perfectly good cellular phone‾
Few are scoffing now. Industry standards enabling handoff between cellular and Wi-Fi networks are in place, and dual-mode Wi-Fi/cellular handset sales - while still a fraction of the massive overall handset market - have continued to rise. ABI Research reckons dual-mode handset sales will top 300 million by 2011.
That said, VoWLAN still faces some crucial technical challenges. One of them is handover between access points (as opposed to handoff from cellular to Wi-Fi) - not an issue when you're sitting at your desk or in a coffee shop, but a pain when you're on the phone trying to walk across the enterprise campus. Handover times can take as long as two seconds, and while AP vendors have solutions for this, all are proprietary.
California-based startup Nuvoiz says it has developed a way around this: a middleware approach that puts the handover intelligence in the handset itself rather than the AP. The reason, says Nuvoiz chairman and CEO Chong-jin Koh, is that proprietary handover means a closed VoWLAN system, which isn't going to fly with users in a world where Wi-Fi is becoming increasingly ubiquitous.
'As a consumer, when I buy a phone, I know that my home has Wi-Fi, and my office has Wi-Fi, and the airport has Wi-Fi, and the coffee shop, and so on, and I want a consistent voice-over-WLAN experience regardless of where I am. If the office WLAN uses, say, an Aruba solution, I can't just buy any phone I want because Aruba has an extension on the client. So there is value in putting the handover intelligence on the handset rather than the access point.'
Nuvoiz already has deals with Alpha Networks of Taiwan to integrate its solution into standalone and dual-mode Wi-Fi handsets, enabling handover times of just under 50 ms. Koh says more announcements will be coming over the next few months.
Nuvoiz's timing arguably couldn't be better. After years of resistance, cellcos are starting to see VoWLAN less as an unfair competitive threat and more as an opportunity - either to offload voice minutes that will become more of a cost than revenue generator as voice goes flat-rate, or to cash in on the inevitable adoption by enterprises. And while femtocells could accomplish a similar feat by providing indoor 3G coverage that also connects to the customer's broadband connection, Wi-Fi is the more mature option for now.
In Japan, NTT DoCoMo and KDDI have launched dual-mode handset services for enterprise users, while Wi-Fi operator Yozan is already offering WLAN as a consumer service. Other cellcos with extensive Wi-Fi hotspot services (like Orange and TeliaSonera in Europe) or enterprise Wi-Fi offerings (like Verizon Business) are planning similar dual-mode offerings.
'I view it as an opportunity because the evolution is going to come whether we actively participate or sit on the sidelines,' says John Shultz, executive director of product management for the managed network services division of Verizon Business. The company is launching a fixed-mobile convergence service in the first half of next year that will include VoWLAN.