There are many reasons an Internet connection will become noticeably slower — including not getting the bandwidth you’re paying for.
Internet speed-testing services might help reveal whether your ISP is at fault, but only if you understand how they work.
When streaming House of Cards, do you find that Frank Underwood can’t make a threat without stuttering? Does uploading a new video to YouTube seem to take forever? Are you really starting to wonder whether you’re getting the faster Internet service that’s costing an extra $50 a month?
There’s probably good reason to wonder. Recent reports show that some Internet service providers (ISPs) deliver slower connection speeds than they claim — up to 41 percent, according to an April 21, 2014, WSJ Digits blog post.
The good news is that there’s a bunch of free broadband speed tests available online. The bad news is that the speed numbers from those tests tend to jump around like a kangaroo on amphetamines. So to start, here are the two most important tips to keep in mind when running any Internet-performance test:
1. Never rely on a single set of readings from a single speed test (more on why below).
2. Local wireless connections have lots of potential potholes that can affect download/upload performance. So run the tests on a computer that’s connected to your network — and the Internet — with an Ethernet cable.
What Internet-performance tests measure
Nearly all Internet-speed tests measure three things: download and upload transfer rates plus latency. The tests are surprisingly simple; download/upload speeds are based on the time required to transfer a single file — or multiple files of various sizes — between your PC and an online server.
The latency (aka ping) test measures the time it takes for a single packet of data to reach an online server and then return to your computer. Latency is typically important to anyone running extremely time-sensitive applications across the Internet — financial trading and interactive games are common examples.