The question of whether you're getting the bandwidth you pay for is one that just doesn't go away. Twice in the last few months
I've suspected my ADSL connection of running slow and, sure enough, despite the modem telling me I had 3Mbps down and 500Kbps
up, for whatever reason, restarting the modem fixed the problem.
I personally blame AT&T for not cleaning the bits as they route
them to me and because of that my modem is getting a build-up
of digital residue.
But testing your connection isn't hard; you can, for instance, use a service like Speedtest.net published by Ookla and let them do the work.
Ookla's Flash-based app figures out where on the 'Net you are, which
of their test servers are nearest you based on ping time,
and then uploads and downloads large files to measure throughput
accompanied by cute graphics (which shows what looks remarkably
like a man peeing on a pyramid ... but I digress).
Speedtest.net tests your connection throughput using a man peeing on a pyramid.
As you can see from the screenshot, my download and upload performance figures are roughly in the expected ranges, though
the scorecard (see image) rather depressingly tells me my connection gets a rating of D-minus and is slower than 77% of other
U.S. connections.
Speedtest.net scorecard
Speedtest.net also has a free iPhone app (which is iPad compatible) that does much the same thing but obviously not using Flash (in case you're not aware, Apple doesn't allow Flash to run on iOS for a number of good reasons, including stability and security issues as well as the fact that Steve Jobs loathed Flash).
Speedtest.net for iOS running on an iPad
The iOS version of Speedtest.net looks much slicker than the Web-based version and, unlike the Web-based version, you can
choose which test server to use. Curiously, the app consistently gives slightly lower throughput values which is, I suspect, due to performance issues
with bulk data transfers over Wi-Fi (the interface also has an "easter egg" ... "pull down" on the meter when not running a test to see a demonic-looking kitty).
The few reviews of this app complain that it isn't accurate, but I found it to be in reasonable agreement with its online
sibling.
The Speedtest.net iOS app reports consistently lower throughputs probably due to Wi-Fi.
Another connection performance test app I like for its presentation is Speedtest X HD (there's a free version and a Pro version for $0.99) published by Veeapps, which also appears to yield similar results to the other tools already covered.
With Speedtest X HD you can select which server to use (a few of them
are only available with the Pro version) and it provides
an interesting display of global performance stats. You can also add
your server, though what's involved in this is not explained
in the app or on their site which is, as of this writing, broken.
This makes me hesitant to recommend the paid version.
Speedtest X HD running on an iPhone
Of course you have to be careful of casting aspersions on your ISP's service when using these tools as they will only give
accurate results if your connection isn't being used by any other applications or services. This is where cloud services can fool you as many run in the background and, while they may adapt to changing
bandwidth usage by throttling themselves, they'll still make your connection look slower than it actually is.
A few weeks ago I wrote about AppNeta and their multi-site WAN and LAN performance management suite and how they used a fascinating technique called
Packet Dispersion Analysis to test and characterize network connections.
To refresh you: Packet Dispersion Analysis sends a sequence of small packets of varying sizes and configurations to a test
server and back again. By analyzing how these packets are delayed and routed by the network it's possible to determine the
latency, the available bandwidth (or "headroom"), the actual bandwidth used, and how well certain protocols (such as VoIP) perform.
The beauty of this technique is that Packet Dispersion Analysis requires only a tiny fraction of the available bandwidth to
work (with AppNeta this is only 20 small packets) so it can be run while routine network operations are in progress without
causing any noticeable bandwidth impact.
AppNeta's PathTest iOS app running on an iPad
AppNeta has just released a new free iOS tool called PathTest that uses the Packet Dispersion Analysis technique and which appears to give more accurate results than any of the other
tools I've tried (what is consistence are my upload speeds, while download speeds, where Wi-Fi is the "last mile" -- OK, last
few meters, but you get my point -- are subject to more complex network effects and so appear to vary more).
While this may not be the sexiest user interface compared to the
others in this column PathTest provides far more detail and
more accurate results. A future update of PathTest promises to scan
your local network and automatically find and save PathTest
targets. PathTest has to be my favorite connection performance test
I've found for iOS so far and gets a Gearhead rating of
5 out of 5.
http://www.networkworld.com/columnists/2013/031313-gearhead.html?page=1
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