Recently, I've been discussing considerations for companies attempting to evaluate wireless networks challenged by multiple standards, uncertain supplier stability, and emerging product architectures.Not only must you figure out which combination of 802.11a\/b\/g to implement in your access points and client adapters, as discussed last time. You also need to find out whether the high-speed networks-11a and 11g-perform as promised.Early anecdotal reports of 802.11a's 54M-bit\/sec coverage and session persistence have been disappointing. And now we are hearing that 802.11g has issues with crowding 802.11b users out of the 2.4-GHz frequency range. In 11g's defense, it is not fully ratified yet, so we are being quick to judge. On the other hand, virtually all wireless LAN vendors have announced 11g products or have committed to delivering them. If there are snafus with peaceful 11b and 11g coexistence, this is a problem.And there are wireless factors to consider other than 11a\/b\/g technology.2.5G and forthcoming 3G and 4G mobile WANs, unlike wireless LANs, operate in licensed spectrum. And spectrum issues abound.Congress and the FCC are supposed to be building a master plan that addresses all spectrum usage-licensed (mobile) and unlicensed (Wi-Fi) alike. Meanwhile, individual senators are hurriedly trying to force through bills of their own to kickstart the economy. So the right hand of the government isn't really in sync with the left hand. Doesn't bode well.\u00a0Disgusted mobile operators are now looking with a softer eye toward Wi-Fi services. Still, Wi-Fi hot-spot services have their own issues, in terms of various emerging supply chain models, the need for more roaming agreements and the need to grow network footprint. Until all that is worked out, your frequent travelers will likely be overpaying, because they can't really purchase a single Wi-Fi subscription that covers virtually everywhere they go.And what device will be best to use for accessing all these networks?You may have read where Proxim, Motorola, and Avaya have partnered to integrate voice over IP, Wi-Fi, and cellular. According to Proxim product manager Maureen Smith, Proxim will supply quality-of-service and Wi-Fi technology and Avaya will contribute VoIP protocols to a whole new breed of phones that Motorola will eventually build ("eventually" being the operative word).However, there are other encouraging signs of integration. Among them: Intel's Banias dual-mode 11a\/b chip architecture, dual-mode adapters from Nokia, dual-mode and dual-frequency phones from Sony, and inter-network roaming software from NetMotion Wireless.