Wireless is well on the way to becoming the default connectivity scheme, for both voice and data, in most business and many consumer applications during the next few years. The idea of a cell as one's only phone no longer seems farfetched; indeed, many people have already made that shift. Dense deployment techniques are providing the capacity that WLANs need to support every service that today wanders happily down a wire. Wide-area broadband wireless-whether 3G, metro-scale Wi-Fi mesh, WiMAX (it's coming, really) and more-will address just about every need a user might have while out and about. That begs the question: Is wire, in fact, doomed?

No, not exactly. The real beauty of wire is its ability to multiply available bandwidth just by adding more wire (or, increasingly, fiber). Wireless is really one big wire in the sky, subject to all manner of regulation and physics. Wire isn't going away, ever. Yet it's clear that wireless is shaping its future.

Example one: LANs. Wireless LANs have to this point mostly been installed as overlays, parallel networks that are configured, secured and managed independently of the wired LAN. This is the best approach in most cases, since it's essentially nondisruptive to the wired net. But with wireless becoming the default in many enterprises, running two parallel networks is a seriously flawed strategy. Maintain two independent network security mechanisms? While this used to make sense, it's rapidly becoming borderline nuts.

Enter the next evolution, the unified WLAN (UWLAN), uniting wired and wireless under a single management structure. Unified switches are basically software-defined and highly configurable to meet whatever the enterprise needs as well as evolving standards. UWLANs are really ULANs-and wireless is shaping the architecture and functionality of this next spin of wireless (and wired) LANs.

Example two: IMS. If you've not yet heard of the Internet Protocol Multimedia Subsystem, you soon will. IMS began life as an effort within the Third-Generation Partnership Project, a trade association looking into higher-level networking protocols and de facto standards for the Universal Mobile Telecommunications System. IMS defines real-time IP-based services for handling voice, video and just about anything else over UMTS. With 3G networks seeing significant buildouts on a global scale, wireless broadband has become a reality.

While there's little doubt that the "IP" in IMS came from the wired world, the robust framework IMS defines for cellular systems is attracting attention from the wireline guys-meaning a standard that originated in the cellular world is likely to be adopted on existing wired networks as well.

There are others, but these two developments alone are indicative of the degree to which wireless is now dominating network thinking overall. What's really interesting, however, is that neither has anything to do with radio. Both basically involve infrastructure and are independent of any particular air link technology. The implications for network design engineers are clear: The chasm that once separated wireless from wireline is closing. The radio part of wireless is but a tiny piece of the solution, and the convergence of the networks behind the last few meters between client and infrastructure will drive product architecture for the foreseeable future.

Who would have thought, even a couple of years ago, that wireless would be in the driver's seat?

Craig Mathias, (craig@farpointgroup.com), principal at Farpoint Group (Ashland, Mass.)