The facts behind your broadband

There are multiple factors affecting the speed of your Internet line. The more you know about what can slow down and speed up your connectivity, the more aware you’ll become of what can be done to optimise your broadband experience, says CAROLYN HOLGATE of MWEB Connect.

The first thing to consider when you think about download speeds is the actual speed of your ADSL line.

If you’re on an entry level 384Kbps line, uploading or downloading large files will take a long time. However, if you were to upgrade to a 4Mbps line your top Internet speed could increase almost tenfold and the time taken to download files would improve accordingly.

There are other issues that can affect your download speeds and therefore your experience of the Internet, some of which relate to ADSL infrastructure and others that relate to Internet Service Providers (ISPs).

An important thing to know about ADSL technology is that it works on a ‚best-effort’ basis, as it can be affected by several infrastructure factors. So, while you may sign up for a 4Mbps line, in reality, you will probably experience speeds slower than this.

A significant factor is the distance between your connection point and your local Telkom exchange. The further away you live, the more your signal will degrade on the line, called ‘line attenuation’. It also brings in the potential problem of electromagnetic interference, called ‚noise’. This affects bandwidth throughput on the line, which results in lower download speeds.

The path determined by Telkom to route traffic from your home to the public telephone exchange before it is passed on to your ISP’s network could also affect speeds. This could make one ISP appear to have a faster download speed than another, whereas it it’s actually a routing issue.

A third factor that could affect download speeds is ‚data congestion’ in the area. The more people in close proximity downloading at the same time, the slower the download speeds will be for everyone in that area. This is called the ‚contention ratio’ (http://en.wikipedia.org/wiki/Contention_ratio).

When it comes to ISPs, service providers can also employ the practice of traffic shaping or traffic throttling, while some ISPs do both.

Shaping refers to prioritising different kinds of traffic on the network and it will affect everyone who is performing a shaped Internet activity, in the same way. Throttling refers to slowing down a user’s Internet speed irrespective of what they’re doing online, so as to reduce the impact of data consumption on the network.

As an analogy, if heavy downloads are trucks and online browsing is cars, shaping means that during peak hours of the day all trucks are limited to the slow lane while cars are allowed to drive in the fast lane. Throttling means during peak times or when you reach a specific data consumption point, both your cars and your trucks are forced to drive in the slow lane.

MWEB shapes traffic but doesn’t throttle it. We believe uncapped, unthrottled ADSL is the best way for South Africans to experience the Internet. Our shaping allows us to prioritise certain traffic like online gaming, email and YouTube to ensure the best possible experience, for our customers.

The best way for consumers to test the practical implications of ADSL infrastructure issues on their connectivity is to ask their ISP to test their line to see what speed it will operate at.

If you want to get ADSL at home for example, call your ISP to check the top speed your line can synchronise at before you upgrade. This will give you a better idea of what package you should purchase.

If you already have a line on the lower end of the ADSL speed range, then it’s worth considering upgrading your package if you want an improved Internet experience. For example, activities like VoIP calls or online gaming perform better on line speeds faster than 384kbps. You will optimise your Internet experience by best matching your ADSL connection with the online activities you’re likely to perform.

Being more aware of the factors that can affect your Internet speed and knowing what to ask your ISP before signing up will give you the info you need to select an ADSL package that best meets your specific needs.

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