The Rort That Is ADSL

Having the sum of five hours of travel to and from work each day leaves me plenty of time to think when I’m not sleeping. The most recent thing I was thinking about was how the promise of fast ADSL speeds are used against consumers.

ADSL2+ speeds can be anything from 1.5Mb to not quite 24Mb, dependant upon your proximity to the exchange. Technically though it’s not a straight measurement between point A and B because your proximity to the exchange is measured by the cable path/length between your modem and the exchange.

ISP’s never tell you where the exchange is. Because of this the speed you actually receive cannot be measured against any benchmark such as this handy graph from Internode:

There are 3rd party tools available to determine where your exchange may be, such as http://www.adsl2exchanges.com.au/, though due to their 3rd-party nature they are not accurate. For example, that site reports that my current connection speed would be 1.5MB  when I have 4MB (thank god it’s wrong!).

Here is where the fun begins: how many people do you think live within 900m of their exchange? How many in terms of physical household size could possible live within 900m of their exchange?

According to ABS data the average new house size in 2002-2003 was 227m² (link) but let’s be generous and say  it was 200m². The area of  a circle with .9km diameter is 2.55km². We can’t assume that the houses and exchange have no roads near them or that the exchange itself occupies no space, and local governments require a certain area of additional land per house,  so let’s deduct 50% of that space to allow for them (this is an approximation). This leaves us with 1.275km² in which, assuming a perfect world where everything fits, we can place 6 residental properties.

Based upon these generous numbers 6 households will receive the maximum speed ADSL offers per exchange, assuming that the cable runs directly from the exchange to each house. The caveat here is that exchanges are not necessarily located in the middle of a residential area. In my case it is located dead in the centre of Campbelltown which is entirely commercial with residential premises beginning at least 400-500m away (in a direct line, not as the cable goes).

2.5km from the exchange, the apex at which you can expect a maximum of half the speed advertised (12Mb), is little better.

Area of circle of radius 2.5km = 19.625km²

Minus the previous 2.55km² = 17.075km²

Allowing for spaces that are not houses (minus 50%) = 8.538km²

Number of houses which can be held in 8.538km² = 42

42 homes can receive speeds ranging from below 24Mb to 12Mb per exchange, assuming that the exchange is situated in a residential area and that each house has a cable running directly from the exchange to the house.

Is selling ‘up to 24Mb’ internet speeds while knowing full well that very few, if any, will ever receive that, or that more than half will be luck to receive 12Mb, deceptive? Hell yes.

I would love to delve further into this by examining ISP pricing and bandwidth costs to understand at what level they set their pricing. I presume this would show that a majority of customers are paying for a price established for a higher amount of bandwidth they are receiving but without the data to back it up this can’t be anything more than conjecture.