O2User: Testing your connection and download speeds

Testing your connection and download speeds
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NewsreadeR on 25 November, 2008 02:45:00
 
What's the difference between connection speed and download speed?
When your router synchronises with the exchange following a reboot or
disconnection it negotiates a connection speed know as the sync. This is
measured in kilobits per second and designated kbps. Two sync rates are show:
downstream and upstream.
Ignoring upstream for the moment, the downstream figure can be considered the
"raw" download speed available and it is not the potential download speed.
The internet uses a transmission protocol known as TCP/IP. This protocol
encloses the data that is sent to you in a wrapper of sorts which carries the
routing information and a number of other parameters necessary to ensure the
data can be reassembled correctly. This wrapper adds an overhead to the process
and uses up some of that raw download bandwidth available.
Typically this all consumes 15-20% of the bandwidth, more if your system isn't
correctly configured (incorrect TCP/IP settings are only really an XP issue as
Vista handles things better). So, in simple terms, you may have a router
downstream sync of 16000kbps but the maximum throughput you can achieve
(download speed) is likely to be ~13500kbps.
How do I find out what my router sync is?
This will depend on the make and model of the router you are using. If you are
using the O2 Wireless Box then you will need to access the router admin pages
which can be accessed via http://192.168.1.254.
To quote O2, "when you first receive your O2 wireless box it is set to a default
username and password to allow you quick and easy access without any need for
additional usernames and passwords". This means access to the Box is wide open
so you are strongly recommended to set a password to restrict access. To do this
go to "User Management" and next to Administrator choose "Change my password".
You'll now be presented with three blank fields. In the first "Old Password"
leave it blank, in the other two type your new password. After confirming you'll
then be asked to enter your username and password. These will now be
Administrator (note the capital A) and the password you've previously entered.
You now have access to a number of functions within the router including the
simple connection stats.
How do I measure my download speed?
The best way is to find a high speed server and download a large file. An easier
way would be to use a purpose built speedtest server, but, when testing download
speeds never rely on just one source of test. Try at least two, one after the
other, preferably of two different types and ensure that the test servers are
known to be reasonably consistent and accurate. I'd recommend the following:
*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)
Note that whilst most such services report the speed in bits (kbps) some
applications report the speed in bytes (kBps - note the capital B). A byte is 8
times larger than a bit so if you see a speed reported as 1000kBps, that
translates to 8000kbps or 8meg as some people call it. Actually, this whole
bit/byte thing can be even more confusing as in technical computing terms there
are 1024bits to a kilobit but some people use 1000. If you use one of the tests
listed above then you'll be comparing like with like with the router so that
shouldn't be an issue.
Why is my download speed so low?
That depends on whether you mean low per se or low in comparison to your router
sync.
If you mean low as in "I'd hardly call this Broadband" then there are a number
of possible reasons, the most likely being that your line is of poor quality or
very long, but that will be the subject of another tutorial.
If you mean the download speed, tested several times and using more than one
speedtest provider, is significantly less than 80% of your sync, then the
following is a list of things to check:
*poor wireless quality signal (ignore what the adaptor reports, that's sinal
strength which is pretty meaningless - try wired)	*incorrect TCP/IP settings (XP
only, try TCPOptimizer)	*something using the bandwidth (other user on LAN, P2p
running, malware)
If you've eliminated those then that leaves network congestion or a fault with
the O2 Broadband service as the most likely problem.