Everyone likes to get something for nothing, so the combination of Internet telephony and open wireless access can seem irresistible. Imagine a wireless phone that can work with networks all over the world, without needing a subscription to a service provider.
Sound good? Well, forget it--at least for the moment. VoIP over Wi-Fi is a budding new technology with a lot of potential, but it's not going to send cell phones to the landfill. Wi-Fi is still designed for the LAN, which makes Wi-Fi telephony a cordless phone technology--and one that's still immature. The IEEE 802.11 standards don't yet cover the QoS mechanisms necessary for high-quality voice, and no phones currently support 802.11i, the security specification that Wi-Fi telephony will eventually depend on.
Still, running voice over 802.11 can be a compelling alternative to cell phones. A TCO analysis by Network Magazine reveals that Wi-Fi telephony can provide significant savings for some organizations--specifically, those with at least 50 staff members who spend about half an hour each day talking on their cell phones, but only while within enterprise premises (see "Comparing the Costs"
That may sound overly restrictive, but Wi-Fi telephony will become more attractive as more advanced phones are released. Like wired enterprise VoIP, it promises increased productivity through convergence. The difference is that whereas regular VoIP improves enterprise telephony by integrating it with computers, voice over Wi-Fi improves it through integration with cell phones. Current Wi-Fi phones offer few advanced features, but the next generation could allow people to use a single number for both their office and cell phone, or to access smartphone functionality such as address books and text messaging while routing calls through the office PBX.
Network Magazine's own reader survey confirms what every 802.11 vendor is saying--namely, that voice over Wi-Fi isn't a mainstream enterprise networking technology now, but it could become one over the next two years. The majority of network managers building Wi-Fi networks say support for voice is an important factor in choosing equipment. That's because Wi-Fi networks designed now will have to work with a new generation of phones expected in 2005.