Full Version: Australia Ponders the Future of WiFi and 3G
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| Most wired users have been attracted to the bright lights of WiFi. The promise of an anywhere, anytime network connection, not to mention spending a few days working from the beach instead of the office, is a compelling argument for wireless computing. But users expecting WiFi to mirror the wired experience have been largely disappointed. Despite a rollout of wireless access points, the wireless network is confined to a number of disparate hotspots owned and operated by a variety of unconnected service providers. Consequently some analysts have labeled WiFi technology by itself a struggling niche application. "People are expecting to emulate the experience they currently get on a wired connection," Lucent Australia & New Zealand director of mobility Chris Coughlan said earlier this year. "What I'd like to see is a ubiquitous offering more in tune with the expectations of 3G, meaning you could get a broadband wireless connection wherever you are without having to choose which network." Several have hinted at a future marriage between WiFi and 3G, although the technical integration challenges are formidable. Meanwhile, unperturbed by the negativity, two sets of service providers in Australia have embarked on ambitious missions to deliver wireless broadband to consumers. With Personal Broadband (formerly CKW Wireless) completing user trials in Sydney for its iBurst service recently, the business case for wireless broadband over 3G seems strong. But collaboration between a number of service providers in Adelaide has also re-ignited WiFi's claim to be an equally viable technology. Agile Communications, AirNet and m.Net Corp., collectively known as AAA Telecommunications, teamed with Cisco, the Adelaide City Council and the South Australian Government to launch citilan, which it claims is Australia's largest public wireless network. Stretching from South Terrace in the city to O'Connell Street in the north, the network comprises 46 Cisco AiroNet access points connected to m.Net's fibre backbone and attached to existing infrastructure such as traffic lights. "During the World IT Congress in 2002, a wireless network was established around Adelaide at the various hotels and venues the congress delegates would be attending," m.Net network manager Lui Iuliano explains. "Based on the success of this rollout, we decided to make further use of the equipment and roll out the citilan network across the city." What is different about this network deployment is the shared infrastructure model adopted by the service providers involved. Putting fierce rivalries aside, the operators collaborated to build a network with the coverage to attract a critical mass of customers. "We recognized we were better off to collaborate on the wholesale level and compete at the retail level," AirNet's operations director Peter Karidis says. "The nature of infrastructure is that it has a high component of fixed costs, so the more people that use it, the lower the cost per user. Ultimately, we expect our customers will have reciprocal access to similar city based wireless networks as they appear across Australia." Iuliano says most of the current interest in the network is coming from ISPs wishing to add a roaming capability to their fixed line Internet packages. "We also have a casual usage plan using premium SMS, where any Vodafone, Optus or Telstra subscriber can send an SMS to a special number at a flat rate and they'll receive one hour of airtime," Iuliano says. While the service is currently free to AirNet and Internode subscribers, Iuliano expects the service to "charge DSL rates per MByte [but] it's up to AAA to make a pricing decision." Because the network effectively recycles access points from the World Congress network, citilan uses 802.11b access points from Cisco. "[However], Cisco is looking at releasing new firmware for the access points that may make them a/b compliant," Iuliano says. The citilan operators aren't worried by the recent successes of Personal Broadband's 3G-based wireless broadband network in Sydney. "The data rates on 3G wouldn't compare. The only advantage would be better coverage by using 3G base stations," Iuliano claims. "They're doing up to 1Mbit/s and theoretically the wireless LAN is capable of data rates up to 11Mbit/s. Typically we're getting between four and 5Mbit/s and that's not just by standing directly underneath an access point." More than 400 users in recent trials in Sydney reported data rates up to 1 Mbit/s in ranges up to 5 km and 600kbit/s seen at a 12 km distance. Some users also experienced indoor penetration from out-of-sight base stations more than 4 km away. Users accessed the network using PCMCIA card modems manufactured by Kyocera. Personal Broadband is now on target for a commercial launch in the fourth quarter of this year. m.Net's Iuliano claims the company has also been investigating 3G. "m.Net has a testbed 3G network across Adelaide," Iuliano says. "The problem at the moment is the limited availability of hardware for 3G. The infrastructure cost is also a lot higher, whereas with citilan we're rolling out access points and connecting to a fibre backbone. There are pros and cons of each one." While the citilan network demonstrates the advantages of sharing the infrastructure cost burden, sharing three RF channels in the 2.4GHz band could well be WiFi's Achilles' heel. Far from the exponential growth curves and hype, analyst firm The Aberdeen Group's digital consumer technology analyst Peter Kastner predicts an "urban WiFi crash" in 2004. "The coming urban WiFi crash of 2004 is not in anyone's predictions, nor is the solution neat," Kastner says. For about $400, anyone can buy an 802.11b access point and wireless PCMCIA card and, with a broadband connection, can hook up their own wireless network. Unfortunately, both 802.11b/g technologies share three RF channels in the 2.4GHz band alongside cordless phones and microwaves with a line-of-sight range up to 100 meters. "The confluence of dense living and the ubiquity of WiFi LAN technology has reached saturation in some places," Kastner explains. "When multiple access points are competing for your laptop's attention, the radio interference causes the laptop to drop its Internet connection and ask you, the humble user, to reconnect. When this happens every few seconds—a scenario we are experiencing now with brand-name equipment—the end of the WiFi world as we know it is imminent." Silicon manufacturers that have incorporated adaptive frequency hopping (AFH) into their products -- whereby the WiFi transceiver hops across frequency channels at up to 1600 times per second specifically to avoid interference with other 2.4GHz devices -- would probably disagree with this doomsday scenario. Just in case Kastner is proved correct though, there is another wireless solution in the 5.4GHz band used by 802.11a, although it's not cheap. 802.11a supports 11 simultaneous channels uninterrupted by cordless phones and microwaves and provides data rates up to 54Mbit/s. According to Kastner, if 2.4GHz has a future, it lies in smarter use of technology. "[For example] Atheros is already extending the range of 802.11b to 270 meters at 1Mbit/s. Companies are also developing software that automatically selects channels, turns down transmit power/receiver sensitivity to the minimum needed for a good link, and are able to reject a foreign signal," Kastner explains. |
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