Fix your broadband

Speed
The most obvious way to measure performance for broadband connections is to look at the overall speed, as quoted by the supplier in Kbits/sec or Mbits/sec.

These numbers are purely figurative; you should not expect to achieve this sort of performance all the time, and may not achieve it at all. This is partly because of physical circumstances - the distance your house is from the local exchange, for example, or the quality of the cabling between your house and the exchange - and partly because of technical and marketing decisions taken by the ISP.

It’s always worth taking the claims of ISPs regarding speeds with a pinch of salt, simply because there’s no way to guarantee them.

To check broadband speeds, go to www.thinkbroadband.com/speedtest.html. The test will take two or three minutes to complete.

Improving the connection
For ADSL, there is not much you can do to fine-tune the connection between the exchange and your home. Your modem or modem/router will locate the best speeds automatically.

Cable connections are similar, but the modem is supplied by the cable company and will typically have just one connector for your PC or home network. The connection between that and your computer is most often Ethernet but sometimes USB, and is intended for connection to a single PC. One thing you definitely can’t do with a cable modem is change the connection speed yourself, although there is a pervasive urban myth that this is possible. Modern cable modems download settings from the cable provider every time they start up – you can’t change them yourself.

Bottlenecks
One of the most common problems with connections is that data being downloaded or uploaded can get stuck in a bottleneck.

Things aren’t as straightforward as the numbers quoted on the packaging, either. For example, an 8Mbits/sec broadband connection at your modem is passed on through a 10Mbits/sec Ethernet port on the modem. This is then plugged into a 100Mbits/sec Ethernet port on a router, which then connects to the PC’s 100 Mbits/sec Ethernet port. From those numbers, it sounds as if the ‘narrowest’ bit of the broadband connection between the internet and your PC is the broadband modem itself. Not so.

No network runs at its maximum rated speed for any individual connection between two points. There are always overheads that slow things down – for example, a Wifi network’s real-life speed is only about half its maximum 54Mbits/sec rating, and the bandwidth available to each connected PC is split between each PC. It’s always good practice to over-specify at each link in the network if you can, and provide as much clear bandwidth as possible. This is particularly true as broadband speeds are increased.

How it all plugs together
Most modern desktop and notebook PCs will come with a 10/100Mbits/sec Ethernet port as standard, and connecting this to a router just involves plugging in the appropriate cable.

Connections from PC to router use Ethernet straight-through cable, as do most connections from router to modem. Don’t confuse this with a crossover cable, which is used to connect two computer directly. Crossover cables are usually marked ‘crossover’ or ‘cross’, but otherwise look identical to normal Ethernet cables.

It’s worth taking the time to check the modem and router manuals to make sure that you use the right cables and plug them into the right sockets. A cable modem’s output should go into the port on the router marked Wan, while the cable you’re plugging into the PC should should go into one of the ports marked Lan.

In an ADSL setup, the router’s Wan port will connect directly to the telephone socket, and the PC cable to a wired Lan port as before.