It’s time for a rational perspective on Wi-Fi

[Commentary] Wi-Fi has so dazzled us with its achievements that many people can’t see its fundamental limitations. Unless network planners and policymakers grasp those limitations, they are likely to reach misguided conclusions about the optimal role of Wi-Fi in our mobile-broadband fabric.

The case for a Wi-Fi-only world is based on false notions that existing wireless broadband providers are less innovative than others within the Internet ecosystem and that networks can grow organically, as suggested by Comcast in its recent pleadings to acquire Time Warner.

The theory is that if government were to give innovators sufficient unlicensed spectrum, a global Wi-Fi network, available everywhere, built by hundreds or even thousands of entities, would materialize, similar to what happened with the Internet. However, because unlicensed bands are short range, any Wi-Fi network, no matter how many hotspots are deployed, will still result in massive coverage gaps.

As serious as the concerns over coverage are the problems inherent to unlicensed frequencies: interference and congestion. Connecting to the Internet via Wi-Fi at hotels and airports, for instance, has become a hit-or-miss proposition. It sometimes works, but more often it’s slow or unavailable due to the escalating number of people using these networks.

A truly ubiquitous, fast mobile broadband network needs both licensed and unlicensed spectrum. Licensed spectrum gives operators manageability and predictability, which enables them to safely invest in a top-down fashion the tens of billions of dollars in the infrastructure necessary for coverage. Given the volume of traffic carried on these networks, these cellular networks will need continually greater capacity. Meanwhile, unlicensed spectrum gives millions of entities the flexibility to invest in a bottom-up manner to provide localized high capacity.

The two approaches are symbiotic and mutually interdependent -- with no foreseeable changes. Both will benefit from technology advances and both will need more spectrum over time.

[Rysavy heads Rysavy Research]