More than a quarter of Wi-Fi products fail compatibility tests first time, according to the Wi-Fi Alliance, the body that promotes Wi-Fi use. Most users find that Wi-Fi devices work first time with any hotspot, however, because the problems are always fixed before the product earns the Wi-Fi badge -- the 1000th of which has now been issued by the Alliance.

"Based on testing of more than 1,000 products over several IEEE (Institute of Electrical and Electronics Engineers) 802.11 standards, products that are prepared for Wi-Fi certification testing fail 25-30 percent of the time or more depending on the technology being tested. Products that do not go through the rigorous testing preparation process have an even higher failure rate," said Wi-Fi Alliance managing director, Frank Hanzlik. "Without Wi-Fi certification, these product failures would have been experienced by the technology consumer."

One of the more successful certification programmes in the industry, the Alliance's scheme has managed to keep the tests stringent enough to actually ensure products do meet the standard and work together, and at the same time get enough products through the mill to make it easy to buy certified products. "It is becoming increasingly difficult to compete globally without Wi-Fi certification," said Hanzlik.

The tests have had to evolve however, and now cover 802.11a, 802.11b, 802.11g and Wi-Fi protected access (WPA), as well as all four in combination. "It is important to remember that Wi-Fi is a very sophisticated radio technology that is continuously being enhanced. New features and the growing number of additional chip sets make Wi-Fi certification more important than ever to consumers and enterprise IT managers," said Hanzlik.

The Alliance maintains a searchable database of certified products. Recent vendors earning certificates in the last couple of months include include 3Com, Accton, Acer, Agere, Airespace, Apple, Belkin, Buffalo, Cisco-Linksys, Dell, D-Link, Fujitsu, HP, Intel, Microsoft, Motorola, NEC, NetGear, Proxim and Sony,