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The Technology Behind The NBN

In recent times the way the NBN is being rolled out has changed, with new technologies introduced to help get the solution available faster and to more people. Unfortunately this now means that all NBN connections won’t be the same and will be different from suburb to suburb or even street to street!

Thanks to PC Authority each of the available technologies have been broken down and rated for us.

The following was posted on the PC Authority website by James Pinnell on 19 April 2017.

Wondering what kinds of speed you can expect from your connection now, and in the future?

We break every part of the technology mix down.

So, you’ve punched in your details into the now moderately useful NBN lookup tool and you’re presented with a rough date – and, finally – you’re presented with the technology that a rough set of roulette wheels working in tandem decided was most adequate for your location. Although there are worst cases, every single technology on the NBN bar one (Satellite) allows for 100mbit plus speeds. But the differences lie in how easily the technology can be upgraded in the future to allow for the much higher speeds necessary for advanced technology needs past 2020.

Rank 1: Fibre to The Premises: FTTP

Fibre to the Premises, as the name suggests, is a direct fibre connection from your closest POI/Node to your house. There is no copper, boosters, or any other sort of additional hardware required. It is considered a “passive” connection in that a single fibre pair is lit at the point of origin and split into multiple connections via unpowered optical splitters that head out to termination points at the user premises.

Around 18% (around 2-2.5 million premises) of Australians will get access to a direct Fibre connection, and although NBN Co offers 1Gbit connection speeds to customers on this technology, no RSPs currently offer this option to customers. Already, NBN is experimenting with symmetrical 102Gbit connections via Nokia’s NG-PON2 standard, which allows for higher throughput via the existing fibre pairs via multiplexing, wavelength magic and a bunch of other options.

Right now, you’re guaranteed – like everyone on a decent fixed line connection – at least 100mbits if you order it. Any long-term speed deviation during peak times would almost certainly not be hardware-related. The advantage of FTTP is that, unlike HFC and FTTN/B/C, the NTU would not need to be upgraded for any future speed upgrades, at least in the next 20 years. As expected, your connection would also be rock solid in terms of stability and require almost zero maintenance in the long term.

Speed by Q4: 100mbit to 1Gbit (Software Capped)
Potential speed in 2020: 10Gbit+ (Software Capped)
Potential speed in 2030:50-100Gbit+ (Theoretical Max without upgrades)

Rank 2: Hybrid Fibre Coaxial: HFC

Around 25% of users (around 3 million premises) will get access to HFC connections.

HFC is, when you break it down to its core, FTTN but benefits from a significantly better delivery system (Coaxial cable, which is a copper line inside a heavy shield of plastic, more copper and an insulator) with active power boosting across the whole connection as well as more robust modulation (RF). The minus to this is that HFC requires a lot of power and equipment to operate, most of which is designed to protect the copper from signal degradation over distance, which occurs when it is unshielded and unpowered.

HFC was designed for medium haul transition, and to mitigate most of the problems that DSL was suffering from at the time. Where FTTN cabinets can’t be more than 300-400m away, cable nodes can be up to 160km away with no speed degradation. Additionally, unlike VDSL2, which is used for FTTN connections, DOCSIS (Data Over Cable Service Interface Specification) has been and continues to be heavily researched and refined (by Cable Networks with a lot invested in infrastructure), and was designed for granular speed increases based on the available amount of bandwidth at the optical node.

Right now, HFC networks can offer 100mbit/40mbit connections easily. DOCSIS3.1, which NBN looks to be switching on later this year, offers a 10x upload speed increase over DOCSIS3, theoretically allowing 10Gbit symmetrical services (10Gbit Down/10Gbit Up) if the node hardware supports it. NBN Co purchased new equipment for the upgraded HFC networks to allow for increased utilisation and capacity, but may encounter issues when their existing nodes are too oversubscribed – fixing this involves a painful process called “Node Splitting,” where new nodes are built and customers are gradually migrated.

NBN’s network design also presents engineering challenges – DOCSIS was never designed to allow choice, as most cable networks lock users to a single carrier. Currently NBN Co is implementing software that tunnels through this system to allow RSPs to offer “Layer 2” services, meaning that customers can use a username and password to authenticate to their provider, rather than being hard locked via their modem. There have been quite a few teething problems as this is basically alpha/beta tested on users.

If you’re interested in DOCSIS and enjoy geeking out on roadmaps and efficiency gains, check out this article, which covers a bit more detail.

Speed by Q4: 100mbit to 1Gbit (Software Capped)
Potential speed in 2020:10Gbit (Theoretical Max)

Rank 3 (Tie): Fibre to the Building/Kerb: FttDp

Around 18% (around 2 million premises) will get FttDp, half FTTC, half FTTB.

As we start moving away from connections designed for long haul and rugged environments and towards FTTN, FttDP is where we begin introducing “traditional” copper into the equation. Like FTTP, Fibre is run all the way out to the basement of an apartment building, or the outside of a premise (usually the comms pit outside or just up the road from a residence) but terminates there and is then jumpered to existing copper via a small device called a Distribution Point Unit.

This method removes the need for large nodes as the connections are individually converted for Kerb sites or split via smaller VDSL2 head end installations in basements. FttDp is still, really, FTTN and therefore it’s included under this heading for stats and guides, but the much shorter copper lengths allow technologies like XG Fast and Vectoring to be significantly more viable. This is due to the lack of noise from competing connections and along with less degradation.

Additionally, the shorter distance to Fibre means eventual upgrades to FTTP are much cheaper and quicker, in many cases just a matter of extending the initial lengths all the way through a few walls or a front yard. Most of the engineering comes into wringing out higher data rates from the copper, and, like DOCSIS, a lot of time and money has gone into isolating and containing the signals carried along the wire.

But speeds are still heavily dependent on copper quality – you could have fibre to your driveway or basement but if you have 50-year-old rotten copper in between you are going to be getting dismal results. Additionally, XG Fast’s lab results that delivered NBN’s 3.5-8gbit speeds were just that – tests. On top of this, they used bonded cable pairs (two copper wires) which most houses don’t have. But the sheer lack of copper in many cases – usually less than 50m to most residents and businesses, is about 250m less than most other users and essentially removes much of the (medium-term) disadvantages. If you manage to get offered this over FTTN, thank your lucky stars.

I ranked FttDp below HFC because of HFC’s medium term speed rankings (it can theoretically reach 10Gbit without any extra last mile wires, whereas FttDp needs bonded copper pairs for its top speeds), as HFC will likely be more consistent as long as the infrastructure keeps up, but in the long run, FttDp is much cheaper to upgrade to FTTP than HFC is.

Speed by Q4 2017: 80mbit to 1Gbit (Software Capped – Good Copper)
Potential speed in 2020:1-8Gbit (Theoretical Max – between 70 and 100m of good copper, possibly paired)

Rank 3 (Tie): Fixed Wireless
Around 3% of users will get access to fixed Wireless connection.

Fixed Wireless involves, essentially, beaming data from a high transmission tower, which is fed by fibre, to an antenna on the roof. Innovations in the last ten years have bolstered a once average option, making it incredibly reliable and robust in comparison to Satellite, which is heavily affected by the weather. Towers can be fitted with multiple radios which allow for a high customer saturation.

Interestingly, if this guide was written before the end of March, Fixed Wireless would be ranked 4th. But recent equipment changes on NBN’s side have doubled the existing offering of 50/20mbits to 100/40mbits, putting Fixed Wireless above FTTN thanks to a very busy and innovative industry.

While fixed line connections are generally better in most scenarios (less latency, better throughput, no antenna faults, no radio congestion, less hardware upgrades on both ends) the sheer awfulness of FTTN coupled with a strong innovation streak in the Fixed Wireless industry means that speeds aren’t likely to be capped as they are with copper.

Speed by Q4: 100mbit (Hardware Capped – Good, Strong Signal)
Potential speed in 2020+:Likely move to Next Gen Fixed Wireless and or/ 5G networks offering 300-500mbit+ speeds

Rank 4: Fibre to The Node: FTTN
Around 33% of users (around 4 million premises) will be stuck with FTTN connections.

The reason there has been so much anger and conjecture around FTTN is that unlike HFC and FttDp, the technology is almost entirely made up of negatives and very, very few positives.

Basically, Fibre to the Node is HFC without the benefits. There are nodes, but due to a lack of amplification on the copper wire, they need to be very close to residences. Because they tap into existing copper and need regular upkeep, they need to sit above ground. Sure, it brings Fibre about 2-5km into communities from the existing exchanges, removing tons of copper from the existing network (literally the only positive), but it still heavily relies on 300-400m of copper that can be easily damaged by weather, animals and human tampering.

The copper isn’t shielded, so it loses signal strength extraordinarily quickly, even when the line is pumped up with vectoring, XG Fast and so on. Too much of Telstra’s old copper is in awful condition and will require remediation to reach even 80mbps. Nodes are ugly, power hungry and take up visual and physical real estate on street corners. They are easily destroyed or damaged, especially in areas with frequent weather events, and to save costs are usually made from plastic/PVC which fades and cracks.

Then there are the speeds. The most optimistic lab tests of noise-blocked, clean, bonded copper sits at around 200mbps. This is within 100-200metres of a node. After 200metres the speed drop is astronomical. What’s more likely is that the average person will probably get around 30-50mbits in 2017, although this may rise once the original ADSL2 network is retired and NBN Co can switch on most of the copper tricks it’s been touting for the past few years which may bump things up 10-15mbps.

The problem is, that’s it. Completely. Copper’s ultimate enemy is distance. Within 100m, there is much more flexibility for higher speeds. After 900m, you might as well be on DSL.

Speed by Q4 2017: 25mbits to 110mbits (Hardware Capped, large amount of dependencies)
Potential speed in 2020+:150-200mbits (Bonded, Copper Pairs, within 200m of Node)

Rank 5: Satellite
Around 3% of users will get access to a Satellite connection.

The only thing worse than FTTN in the speed stakes is the Sky Muster service, but in all honesty, that’s not the fault of NBN Co. In fact, the two Satellites that NBN owns are cutting edge – beaming down packets from space to parts of the country that couldn’t even get a basic dialup service.

Satellite is simple in practice – you put a dish on your roof, point it at the Satellite and you can beam data back and forth. For many who were stuck on 56k connections or very expensive 3g/4g wireless, Sky Muster’s 25/5mbps is almost revolutionary. Hell, it’s faster than many Sydney metro customers got on ADSL. However, weather is a big problem – very cloudy and rainy days may equal little to zero data transfer.

Sky Muster speeds, and their limited data plans, will likely be in place for the foreseeable future. Unless a future NBN CO decides to replace the Satellites once they eventually fall out of the sky, however.

Speed by Q4: 25mbits (Hardware Capped, Good Signal)
Potential speed in 2020+: See Above

Two-thirds of Australia will roll the dice and end up with a 100mbits+ connection. One third will not.


So the million dollar question is – What will I get?

If you wish to know the technology used at your location, visit the NBNco website here and enter your address details. You will be provided with a time-frame for availability, and the technology that will be used.

If you have any questions, you are welcome to call our office on 1300 799 928 and speak to your account manager.