[LINK] Turnbull's NBN

Paul Brooks pbrooks-link at layer10.com.au
Wed Apr 10 10:26:21 AEST 2013


On 10/04/2013 12:45 AM, Glen Turner wrote:
> On 09/04/2013, at 1:51 PM, tomk wrote
>> Speeds over Copper now rival and exceed those over the Aussie NBN specified fibre.
> For the typical copper lead-in to a house you're looking at a maximum data rate of 50Mbps asymmetric. That's not actually available right now in shipping equipment.
>
> The NBN-installed fibre can run up to 10Gbps asymmetric. However the lasers and receivers for this are expensive. So the question is how slow to run the NBN last mile fibre so that it results in a service which is cheap enough for householders. NBNCo have decided that they will use 100Mbps lasers and receivers.
You're being a little pessimistic there Glen!. The fibre could run up to terabits,
depending on what equipment is used to light it up. NBN Co have decided to slow it
down and use 2.4 Gbps lasers and receivers in GPON equipment which is readily
affordable now, and upgradeable to XPON (10 Gbps lasers) in the near future when the
prices for this kit comes down.
The NBN Co NTU is equipped with Gig Ethernet hardware electrical ports for the user
equipment to plug in to, and have chosen to limit the top speed these to 100 Mbps in
this first phase, expecting to allow them to be unthrottled and operated up to 1000
Mbps once the backhaul network has been built to cope and they release those plans.

With the equipment being installed right now, and the release of 1000/400 plans next
year, NBN CO could deliver 2.4 Gbps across 3 hardware ports to a single home (but then
none of the other 15 homes on the PON would get anything).
Without the software tweak, a house could today get 400 Mbps just by ordering 4 x 100
Mbps services on their NTU, and more if they wanted to go through the hassle of having
a second NTU installed to get more ports.

This is roughly a hundred times more than anything that can be done with two
un-twisted phone-grade copper pairs - there is nothing on copper that rivals or
exceeds this.

75% of the cost to build 70% of the network in 80% of the timeframe to provide less
than 10% of the capacity - visionary.


Paul.




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