Hints and Tips - Interpret Speed Test Results Correctly
There are several On-line Speed Tests just one internet search away and they provide a very useful service. They can show that a network that is performing well is performing well and how much it is performing well.
However on a network that appears to be performing badly the value of such tests can decline rapidly
When I worked for a multi-national I once had a call from an irate manager of one of our sites in India: "Your network is broken - I have half a dozen of my developers here running speed tests and they're only getting 100 bytes per second!"
Fortunately I was able to point him to the web page on my network monitor that demonstrated that, in fact, the network was transferring data at its maximum specified rate and appeared to be slow only because it was overloaded.
Then came the tricky bit which was to mention that having several people running speed test simultaneously only exacerbated the problem: The test downloads and uploads a large amount of useless data and times how long it takes. This puts even more strain on an overloaded network.
Their time would have been much better spent working out if this period of very high network activity was normal and therefore would justify an extremely expensive network upgrade, if it was routine but not urgent so could be scheduled to run outside business hours, if it was a rare, but predictable, event which in future could be mitigated by warning users in advance and managing their expectations, if it was a one-off transfer vital to business needs or if it was just someone downloading a movie.
At that time our monitoring facilities were not up to identifying traffic down to this level of detail, and this event served as a great wake-up call.
Moral: Use Speed Test applications to brag about how fast your network is. Never use them to fault-find a "slow" network unless you know you are the only network user.
