The NBN may now have gotten the go-ahead, but it's probably going to be years until fibre-optic cabling passes your house. In the meantime, the only way you're going to see NBN-like speeds in the 100Mbps range will be over cable infrastructure — if you can get it. But whether it's delivered over fibre or cable, what does the increased speed rating really mean in everyday usage? We set out to find out.
We were recently offered a trial of Optus' new Supersonic Broadband service, which uses the DOCSIS 3.0 cable modem standard to boost the peak speed of Optus cable services in parts of Sydney, Melbourne and Brisbane from around 20Mbps to 100Mbps (Telstra offers a similar service, called BigPond Ultimate Cable, in parts of Melbourne).
Optus has matched Telstra's 100Mbps speeds, but warns they're only relevant for Australian content. (Credit: Optus)
DOCSIS 3.0 is the latest iteration of the ITU-endorsed international standard used to move data to and from cable modems around the world. DOCSIS 3.0 was released just over four years ago, but has only been available in Australia since late last year. DOCSIS provides up to 42.88Mbps per communications channel, and DOCSIS 3.0 added "channel bonding" that combines several channels to produce maximum service speeds of up to 160Mbps downstream and 120Mbps upstream. Previous versions supported just one channel in each direction.
Overall, the faster service was responsive and snappy, with many pages loading quickly and streaming video starting pretty quickly. We were able, for example, to watch 1080p YouTube videos at full-screen resolution with minimal buffering, and jumping to unbuffered parts of the video took less than a second before buffering was complete and the video could resume playing.
So it handles well. But how fast does it go?
Using a Speedtest.net server from our test site in Melbourne against an Optus-hosted server also located in Melbourne, benchmarking repeatedly clocked up speeds of up to 101Mbps downstream and around 1.7Mbps upstream, confirming the service is performing as expected (unless, that is, you expected faster upstream performance).
(Screenshot by David Braue/CNET Australia)
The companion Pingtest.net showed pretty low latency, with testing to Sydney showing pings of 51ms and 7ms jitter. This reflects the time it takes for distant servers to respond to requests for information, and gave us a score of "B" that indicates most applications would work fine, save some time-sensitive online games. Ping results are directly related to the performance of things like streaming video and online gaming, so low ping times are a very good sign that the Optus service is both fast and correctly provisioned — at least, within the same city, and with the fewest possible router hops.
(Screenshot by David Braue/CNET Australia)
Confirming this, a Pingtest.net run to Canberra servers produced ping times of 36ms and 4ms jitter, scoring an "A" grade.
Using other Speedtest.net servers, however, throughput dropped considerably. For example, benchmarking a server in Sydney delivered just 78.04Mbps even though the traffic was still on Optus' network, while transfers to an Optus server in Brisbane delivered just 22.17Mbps. Clearly, performance varies quite considerably depending on where the websites you're visiting are located.
The results got worse when we ran Speedtest against a range of international destinations. We were, for example, only able to get around 5Mbps from Palo Alto, in the heart of Silicon Valley, with upload speeds basically the same as we got for domestic traffic. However, latency was significantly higher across the pacific, at 180ms to both cities.
We had similar problems with traffic to Europe: we could only get 2.33Mbps downstream from London and with 632ms latency, while connections to countries like Mali and Brazil actually turned in faster download speeds, albeit poor upload and latency statistics. See the table below for the full results.
|Palo Alto, USA||5.07Mbps||1.47Mbps||177ms|
|Los Angeles, USA||4.77Mbps||1.41Mbps||180ms|
|New York City, USA||2.11Mbps||0.91Mbps||253ms|
|St Petersburg, Russia||1.61Mbps||1.07Mbps||363ms|
|Cape Town, South Africa||1.12Mbps||0.74Mbps||483ms|
|Rio de Janeiro, Brazil||3.87Mbps||0.30Mbps||757ms|
Speedtest.net results to various destinations over 100Mbps (peak) Optus cable internet service. Results recorded on 7 September 2010.
These figures reflect a startling truth that only becomes clear when you've done the benchmarking: you may be able to get tens of megabits per second domestically, but once you're looking for content offshore, you are very, very limited by the speed of the overseas links connecting us to the rest of the world.
Apart from Singapore, New Zealand, the US and South America, we were unable to get more than 5Mbps download speeds outside of Australasia. And this will not change, no matter how fast your domestic connection is. Optus acknowledges this in the small print of its Supersonic Broadband advertisements, and they're not kidding.
The hard truth about 100Mbps internet
This brings us to a dirty little secret: for the majority of everyday online tasks, 100Mbps cable internet services just aren't any faster than normal cable internet services (our cable service was clocking up speeds of around 18Mbps before the upgrade). If you're one of the lucky people who already gets more than 10Mbps over ADSL, you probably won't notice the difference either.
We confirmed this by doing a number of everyday tasks before the upgrade, and after it.
For example, to fill the link, we tried downloading a gigabyte-plus Linux ISO image via BitTorrent to see how it performed, and were able to get up to 1.7MB/sec throughput with a single file and a touch over 2MB/sec while downloading three torrents simultaneously. The thing is, these speeds were similar both before and after the 100Mbps service was switched on.
BitTorrent performance was the same over 18Mbps and 100Mbps connections. (Screenshot by David Braue/CNET Australia)
One place where performance seemed a little snappier was on YouTube: when watching a streaming 1080p sample video, performance was smooth and the video was quick to re-home when we jumped to a part of the video that hadn't been buffered yet.
We tried watching streaming TV on the ABC's iView service, but found no real improvement in its quality. A click on the site's Bandwidth tab showed why: the ABC's connection maxes out at 9.2Mbps, which is well below the capacity of our link to the ABC but reflects the ABC's need to limit how much data it sends to any one viewer.
As the ABC iView's Bandwidth meter shows, even Australian-hosted sites can only push out content at a certain speed — and it's way slower than 100Mbps. (Screenshot by David Braue/CNET Australia)
One problem with 100Mbps services is that normal traffic like web surfing simply doesn't come anywhere near saturating the connection; indeed, we generally saw almost no improvement in web surfing speed, but in most cases ended up waiting for the pages to load as the limitations of the remote server's connection became clear. Clearly, commonly-held wisdom that the NBN is only for downloading pirated movies and porn faster, is completely incorrect — unless that content is hosted in Australia.
We tried similar benchmarking over a Telstra Next G connection that turned in Speedtest.net figures of around 2.5Mbps, and we were still able to stream video with surprising quality — albeit with a few stutters as we had to wait for the connection to buffer itself again. However, the higher latency and overall slower performance confirmed that wireless 3G services are still a pale competitor to the kinds of speeds the NBN will deliver.
Bandwidth for tomorrow
If you're currently struggling along with dial-up internet, wireless broadband or even ADSL2+ services running at a few Mbps, the speed improvements offered by 100Mbps cable will blow your mind. However, you may be equally impressed just by switching to normal cable services, too. If you can get those services, that means you're in a cabled area — and you should probably already be a subscriber to cable-modem services. We advise that you run, don't walk, to the phone and get your cable service connected.
For now, however, you may find the standard services — 20Mbps on Optus and 30Mbps on Telstra — more than adequate. The only time now, 100Mbps services will really speed your performance is if you're comparing them to an absolute low-grade broadband connection, or if you're accessing content hosted or mirrored within Australia.
So, if 100Mbps internet isn't really faster than the alternative, does this invalidate the case for 100Mbps internet, and by extension the entire NBN? Not at all.
One of the biggest problems with current internet services is that they're a best-effort case — and often, ADSL's best effort is really not very good at all. Switching to 100Mbps services, whether carried via fibre or cable, will ensure that your household has enough bandwidth headroom that it can take advantage of whatever the internet has to offer. Note also that there is every sign that slower (and cheaper) NBN services will also be on offer: early plans offer 25Mbps and 50Mbps as well as 100Mbps and the eventual maximum of 1Gbps.
But if 100Mbps doesn't speed things up, how will 1Gbps make any difference? The answer is simple: it won't — at least, not just for you. The key here is to think in terms of aggregate bandwidth than the experience for any particular user. This will particularly help households with more than one computer, where simultaneous access to streaming video can quickly saturate the home connection.
A 100Mbps connection means you can have a high-definition video stream running to your house 24/7 for playing on your computer or TV, without affecting anything else that you might need to do over your internet connection; a slower connection may not only struggle to keep up with the video, but would see other speeds degraded as bandwidth contention kicked in.
Remember that in this day and age, "computer" is an increasingly broad term. Today's TVs, PVRs, Blu-ray players and even internet-radio-enabled clock radios are commonly shipping with internet connectivity — downloading data in the background that you may never notice until it slows down your normal internet activities. Apple's new Apple TV, for example, is entirely built around the idea of streaming HD video in real time — and that's going to require fat pipes and a pretty generous quota.
This leads us to the unavoidable truth of 100Mbps broadband: if your household is getting more and more connected, a 100Mbps connection is an excellent way to ensure that there's enough bandwidth to go around. A wireless service will never provide comparable speeds and performance — so if you're currently on ADSL and can make the switch to cable, it's well worth it.
If you're currently on ADSL and have no option, hope that a fibre NBN gets to your house sooner rather than later — then sign up for a 25Mbps fibre plan that will, unlike with ADSL, give you the speed you paid for. But if you're just one person on a computer, and you get your TV the old-fashioned way, there's probably still not enough in the new services to justify the price premium that 100Mbps cable demands.
Watch the video above to see the fast cable service compared to both standard cable and Telstra Next G wireless. See how it affects typical activities like web surfing, watching HD video and bittorrent downloading.