WiFi's short range was its weak point from the start, until mesh networking came along. After the more serious security and quality problems of mesh technology were addressed, the technology became popular in campus-wide and metro-wide deployments. So much so, in fact, that WiFi providers have been touting the technology as an alternative to cellular, what with WiFi's lower monthly fees and higher bandwidth compared to cellular providers for services such as Internet access, VPN connections to corporate networks and VoIP calls. These services are now being aggressively marketed both to businesses and individual mobile users. To deliver these services, 802.11-based mesh networks are being set up to blanket large areas (the latest example: The Wireless Access Zone Tempe [WAZTempe] network, completed just last week by network operator NeoReach Wireless, a division of MobilePro). As is the case with all such networks, WAZTempe operates in the unlicensed 2.4-GHz and 5-GHz radio bands.
Not everyone agrees that WiFi is truly an alternative to cellular. The Yankee Group just issued a report called "Myths and Realities of Wi-Fi Mesh Networking," with its conclusion well summed up by co-author Phil Redman: "There is a limit to how far you can push an unlicensed radio technology." This is true even as the pace of WiFi innovation--consider 802.11n, which promises bandwidth of 300 Mbps to 400 Mbps in 2007--accelerates and allows providers to push that limit.
Providers such as NeoReach and vendors such as Strix, Tropos, BelAir and others, argue that the many metro-area deployments around the U.S. offer evidence that WiFi mesh networks are viable. "If we're talking about just the technology, then these types of networks designed to cover what I call 'localized regions,' with the intention of having a modest level of usage, make sense," Redman acknowledges. Whether WiFi networks can succeed as sustainable businesses is unclear. "It's very difficult for a [Wi-Fi] business model to work in isolation from another service that has a reasonable level of market scale" such as wide-area cellular services, he says.
Bob Egan, an author of the original 802.11 standard and now director of emergent technologies at consultancy Tower Group, is also skeptical about WiFi mesh being able to deliver for mobile enterprises. "802.11 was never intended and will never be a metro architecture," he says. "Metro [WiFi] nets are just a venture capitalist wish, and not an architectural reality."