What, exactly, is Cable Broadband?

  • Speeds can be high, but inconsistent
  • Only available to about 25% of homes
  • Telstra and Optus offer cable plans

Your writer’s first job in telecommunications was in cold calling homes in 1998 to arrange an appointment for a salesman to come talk to you about broadband. We worked for Salesforce, an outsource call centre in Carlton, VIC (a suburb of Melbourne) that leveraged its strong relationship with Telstra to expand and become one of the biggest call centre operators in the world.

    hfc cable


We would call homes between 5pm and 9pm and talk about the wonders of a high speed connection to the web. 56K? Try 8000K. And all for just 99 a month, with a massive 100MB download allowance! It was such an exclusive product, with a tiny rollout footprint around target areas in Melbourne and Sydney, that one of the numbers on my callsheet wasn’t even an address – it was just ‘Raheen’, the home of Richard Pratt, one of Australia’s wealthiest men (for the record, his butler didn’t go for it at the time, but said his IT people ‘would look into it’).

Telstra’s rollout of Cable followed that of Optus, the purpose-built competitor developed with a handful of Australian, British and US companies to challenge the newly part-privatized Telstra. Optus had to roll out their network to provide anything to customers – Telstra stymied any attempt to offer access to their copper telephone wire network, effectively leaving Optus with no choice but to roll out an alternative. Optus’ network was built for Pay TV and telephony; broadband was still considered a novel third option.

Telstra’s rollout eventually eclipsed Optus’, which abandoned their network when Telstra opened their telephone network to wholesale access (at the behest of regulators, natch) and concentrated on Digital Subscriber Line (DSL), the popular choice in the US (even though cable is far more ubiquitous there).

The Cable networks became a kind of boutique option, available to only 30% of homes, all concentrated in densely populated centres of Melbourne, Sydney, Perth, Adelaide and Brisbane. With the development of single homes into multi-dwelling units, and with most developers not willing to split the wire to each individual unit, that number has now dropped to about 20-25% of homes with Cable access. Similarly, these two networks can carry Foxtel Pay TV services, but were abandoned for further development in favour of cheaper and easier to implement satellite connections.

What is Cable?

The Cable networks are commonly referred to as Hybrid-Fibre-Coaxial, or HFC. This means that each connected home has a thick guage copper wire (known as RG6 Coaxial) leading to a connection point in a neighbourhood, usually a small box serving about 400 homes. The box then aggregates these connections to a fibre optic link back to a network head point (usually somewhere in the CBD of that city).

To this end, they’re not terribly different in the fundamentals to a DSL or even to a mobile broadband link. DSL uses a standard copper telephone wire to link back to a telephone exchange, which aggregates those connections to a fibre optic network as well. Even mobile broadband, in some areas, uses the mobile wireless link to a tower, and the tower is fed by a fibre optic network.

But because the guage of the wire is thicker, and the average length to the box is shorter, Cable can achieve much faster speeds (this is a gross oversimplification, but it’s at least partly accurate).

The current DOCSIS 3.0 standard has been rolled out to most of Melbourne and Sydney’s networks on both Optus and Telstra, offering speeds of 100 Mbps. This is much faster than the highest achievable speed over ADSL2+, which is 24 Mbps.

So why wouldn’t I get it?


Apart from the scant availability of Cable Broadband,  the main problems people have with it are cost and instability.

Optus and Telstra have both managed to fend off regulators who want them to open their cable networks for wholesale competition. So Optus and Telstra are the only ones who offer it, and they’re typically much more expensive than the competition. Of course, that competition (including TPG, iiNet, Internode and iPrimus) only has access to DSL.

The higher monthly cost may be justifiable in light of the faster speeds, but the other issue is that both companies are fond of burdening their cable service with 24 month contracts, no exceptions (Optus has become more flexible). Telstra, especially, is also fond of requiring that customers get a landline phone with their service, whether they need it or not- which makes sense with DSL, since that requires an active telephone line as part of the service, but just appears greedy when talking about two fundamentally unrelated services.

As for speed – ADSL2+ is slower, but your speed tends to be consistent. As your connection is just yours, all the way to the exchange. With cable, you share your connection with potentially hundreds of other users in your neighbourhood – and both Telstra and Optus have failed to adequately meet demand for bandwidth across this network in recent years. So Cable is famously erratic, hitting unusable speeds in the evening when everyone gets home and hitsup bit torrents to get the latest TV shows.

Why have they dropped the ball?

HFC Cable is going to be dismantled, as part of the current plan for the National Broadband Network. The NBN will aim to provide fibre to each home, rather than a mixed network. Telstra is keeping their interest in the HFC network for Foxtel, but Optus have sold their network to NBNco to be folded into the NBN.

The coalition plan is to implement a similar technology called Fibre to the Node, which will bring fibre to every 200 homes or so with a much higher capacity than cable – and keep HFC around for those areas that have it. Most industry professionals believe this  will cause a bit of chaos, especially since the coalition has pledged to not disrupt the contracts in place for Labor’s much more comprehensive fibre-to-the-home rollout, in place for 40% of homes. It would mean a patchwork networkof some blazing fast, easily scalable FTTH; a less impressive but still next-gen prtion with fibre to a local node, and a bunch of metro customers on 20 year old, outdated HFC connections. It would be messy, and it would require that several flat buildings and the like, who have fibre in the street but not wired to each apartment, will need significant development.

Can I get Cable at my property?

Call us on 1300 106 571 - we can do a check to see if cable is available by providing your full property address.

If Cable is not available we can also check if the NBN or ADSL2+ is available which are your next best options.