It’s extremely likely that sometime in 2014, the number of internet users will pass 3 billion. Not surprisingly, the largest areas of growth are developing markets—predominantly Africa and the Asia-Pacific region. These markets are being flooded with mobile devices small and large, fast and slow, smart or otherwise.
Connectivity in these regions is of great interest to large tech companies scrambling for control. Today, however, bandwidth is limited, reliability is questionable, and data plans are small. Even in markets saturated with mobile usage, like the US and much of Europe, connections are often flaky and unreliable.
For all those reasons and more, now is the time to test what you build in sub-optimal situations. Thankfully, there are a handful of tools that can help you do just that from the comfort of your high-bandwidth connection and favorite chair, rather than trekking out to a remote field with a Faraday cage.
Slow your roll
If you’re using Grunt or Node.js, there’s a fantastic plugin and module, respectively, that can slow your local server’s connection down to a configurable speed. It’s a great start to network performance testing, but it’s fairly one-dimensional.
Charles is a more robust throttler exposing a lot more control. In addition to amazing tools allowing complete insight to all network requests, Charles can throttle your entire connection, so when enabled, all traffic in and out of your machine is affected. Throttling isn’t the only factor of network performance, however. Latency is a major contributor, and Charles provides control over that aspect, as well.
Unfortunately, these tools don’t expose control over the final, and potentially most important aspect of network performance—packet loss. It has always been the toughest aspect to simulate, but if you’re a Mac and/or iOS user, you have access to the Network Link Conditioner. With control over upstream and downstream transfer speeds, latency, packet loss, and even DNS delay, Network Link Conditioner is a super-powered system-level tool that will fundamentally change the way you build and test things.
Apple provides the Network Link Conditioner through their developer platform, and luckily, it’s accessible through the free developer program, so you don’t have to pay to use it.
The Network Link Conditioner comes with some built-in presets to match common connections, such as EDGE, 3G, and DSL. You can even create and save your own presets, allowing you to easily switch between connection levels for fast testing.
All of these tools open up a new realm of testing and optimization available to us, and as the world changes, network performance testing becomes more and more important. Have you used any other tools or techniques for testing? Share them below in the comments!
Nice!
I often find Charles to be too much tool for my needs — I recently came across Slowy for OS X, which works well for simple bandwidth throttling when I don’t need to complexity of Charles.
Note that good old Fiddler also has a “modem speed” mode which cripples your connection very well.
I haven’t had a chance to try it yet, but did find this for linux as well. http://www.linuxfoundation.org/collaborate/workgroups/networking/netem
I did a little wrap up a few weeks ago which is Mac specific that offers a little insight to some other options – Throttle Bandwidth Testing.
On the Java side of things there’s a project call Slow Light (https://github.com/tacitknowledge/slow-light) that degrades performance within a Java application. There’s a sub project called Slow Light Proxy Server (https://github.com/tacitknowledge/slow-light/tree/master/proxy) that is particularly relevant here.