Chapter 5. Carrier Networks: Down the Rabbit Hole

Tim Kadlec

There’s a point in Lewis Carroll’s Alice's Adventures in Wonderland where Alice believes she may never be able to leave the room she has found herself in after following the rabbit down its hole. She starts to question her decision:

I almost wish I hadn’t gone down that rabbit hole—and yet—and yet—it’s rather curious, you know, this kind of life.

The world of mobile performance can feel the same—particularly when you start to explore mobile carrier networks. If you’re looking for consistency and stability, you should look elsewhere. If, on the other hand, you enjoy the energy and excitement found in the chaos that surrounds an unstable environment, then you’ll find yourself right at home.


The complexity of a system may be determined by the number of its variables, and carrier networks have a lot of variables. Their performance varies dramatically depending on factors such as location, the number of people using a network, the weather, the carrier—there isn’t much that you can rely on to remain static.

One study ( demonstrated just how much variance there can be from location to location. The test involved checking bandwidth on 3G networks for three different mobile carriers—Sprint, Verizon, and AT&T—in various cities across the United States. The diversity of the results were stunning.

The highest recorded bandwidth was 1425 kbps in New Orleans on ...

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