Wireless Use of the Wireline Network

It is a relatively common misconception that when you place a call on your wireless phone, the call travels through the air, riding the waves of spectrum until it arrives at the call’s destination.  The reality is far more complicated.  Not only do wireless calls rely heavily on the wireline network, in many instances the only wireless portions of the call are from the originating handset to the nearest cell tower, and from the cell tower nearest the call recipient to his or her handset.  (And in the case of wireless to wireline calls, the wireless component is even less than that!)  You see, even wireless needs hard wires or what we call “wireline” to complete a wireless call.

When you initiate a wireless call, the signal travels through the air (via a wireless connection) to the nearest cell site, which then transfers the call to the nearest mobile switching center, or MSC.  Typically, this exchange is accomplished through wireline (or landlines) facilities provided by local exchange carriers and interexchange carriers.  The MSC then determines where the call needs to be routed—to the recipient’s landline phone, to their wireless phone near their home location, or to their wireless phone somewhere else,even thousands of miles from their home.  The call is then carried over the wires of the public switched telephone network to the end user.  (The public switched telephone network, or PSTN for short, is simply a catch-all name for the telephone network you use every day to complete local, long distance and international calls.)  The entire procedure, while incredibly complex and precise, is accomplished instantaneously without the awareness of either party participating in the call.

Providing high-quality wireless service in rural areas presents numerous specific challenges.  As a result of lower population densities, each cell tower serves fewer end users, and thus the cost per user is significantly higher than in non-rural areas.  Rugged terrain means that towers must be placed closer together, and often built taller than those elsewhere, again increasing costs.  Given these daunting challenges, it is even more critical that rural cellular providers are able to rely on a solid wireline network to allow them to serve their customers.  Rural wireline providers have proven themselves up to the challenge–the end result is a wireless network which succeeds because it works in tandem with a wireline network that is the envy of the world.

(This article was written by NTCA Economist Rick Schadelbauer.)