All about speed tests

[Saturday]

Everyone wants to do it: you've just got your new broadband connection and you want to know just how fast it is; or suddenly, things don't seem so fast any more and you want to know whether you're imagining it. The answer? Run a speed test!

Well, maybe.

The problem with running a speed test is you're not just running a test of your ISP's network speed. You're testing:

• your PC and it's load,
• your LAN and its load,
• the connection between your PC and the router
• the connection between the router and the exchange
• your ISP's equipment and network
• the link between your ISP's network and the speedtest server you're connected to
• the speed test server and its load

How much of that is down to your ISP? Not all that much actually.

So, to really get an idea of how well your ISP is performing you must do the following:

• If using XP, ensure your TCP/IP settings are correct for a fast connection. TCPOptimizer is a popular tool. With Vista it is best to leave things alone as Vista will be correctly set up by default. If you're running a MAC, that's likely to be OK too.
• If you're using wireless to connect to the router, temporarily set up a wired connection. A poor wireless quality connection is the number one reason for incorrect speed test results. Don't believe what your wireless adaptor says. It's reporting signal strength and signal quality is what matters.
• Before running a test make sure there is nothing else on your PC currently using the internet e.g. P2P, downloads in background etc. Then make sure no one else on your LAN is either.
• Don't rely on one server for a test. Server overload is the number two reason for incorrect speed test results. Try at least two different speed test servers and make sure they are known to be load tolerant (see below).

Which are the best speed testers?

Opinion will always be divided on that question and people have their favourites. Also, the more popular servers get the more they'll struggle with overload, particularly at peak times.

Personally, I think the following are fairly reliable:

• o2user's speedtest (this spreads downloads across a number of servers so doesn't usually slow down at peak time)
• Be's speedtest (O2 is on the Be network so this may give an idea of network load)
• Giganews speedtest (use the European server but expect some peak time slowdown)

There are plenty of others. Namesco and Speed.io are both worth considering. The latter being new to me but appearing (currently) to be performing well.

What else?

Well here's possibly the most important part. You may well have bought an "up to" 8meg or 16meg sevice, or even an ultimate 24meg service but the key words there are "up to". ADSL is a line length and line quality dependent service. If you have a poor/long line it doesn't matter what you've bought, ADSL can't deliver full speeds.

Lastly, please remember that speed testers measure throughput and your ISP has sold you a sync rate. They're not the same thing and typically you'd expect your throughput (speed test result) to be approximately 80-85% of the sync rate that your router is achieving. How do you find your router sync and why is it different to throughput? See here.

[k1w1]

Can the BT Speedtest be used by me? When I was with Sky, I used it a few times, but now I cant seem to get on. any help with what to log in with would be much appreciated.

[Saturday]

Which BT test do you mean?

There's one that can only be used to test a BT internet connection e.g. BT's own or rebadged such as O2 Home Access, Sky Connect etc?

According to your profile you're on O2 Standard which is an LLU product - the BT speedtest can't be used for this.

If you're looking for other speedtest sites then Namesco and speed.io are quite popular and reasonably accurate - most of the time. For a different type of speedtest try Numion Yourspeed and choose "quickstart". Remember though that all speedtesters have flaws.