[AusNOG] Swap Beer for Doubling/Tripling Included CVC

Glen Turner gdt at gdt.id.au
Sun Mar 22 18:29:18 EST 2020

Troy Baird wrote:
> There are options for cost effective smaller 10g fanless switches
> that are perfect for this situation....

Passive DWDM optical systems work too -- no electronics in the street
at all, and so no need for expensive provision of roadside electricity.

DWDM gear is normally pretty expensive, but that's because the parts
are traditionally long-haul (high powered lasers, sensitive receivers,
low loss optical muxes). If you plan for a reach of 10Km then the parts
are only slightly more than the equivalent-speed 1310nm part.  That
means that 1Gbps would be the current sweet point for domestic
connections, and 10Gbps for local schools and network-centric

Such a design would have meant that NBNCo's task would have been to get
a 100GHz channel of light to each house or apartment. What happens from
there would then be up to the ISP (lighting at 100Mbps, 1Gbps, 10Gbps,
25Gbps; using a switch port per client, or using a PON-style optical
bus for a group of 'value' clients which then contend for the switch
port).  Very much a financial model like the twisted pair last mile --
the last-mile carrier gets a fixed income per DWDM channel and charges
for exchange space; the ISP turns those fixed raw materials into a
range of products (1Gbps contended, 1Gbps dedicated, 10Gbps dedicated,
10Gbps dedicated redundant, and so on).

Muxes also allow a north-add-drop and a south-add-drop for each
channel.  So if the two ends of the trunk fibre run to different
exchanges then these systems naturally provide redundancy -- each
premises sees a channel north and a channel south. A domestic premises
might well chose not to increase its telecommunications costs and so
populate only the north-facing channel. A business might choose to
populate both the north-facing and south-facing channels, paying their
ISP more accordingly.

I've long stated my belief that the design choice for a National
Broadband Network wasn't copper versus fibre; but an optical network
with active equipment or an optical network with passive equipment. 
Many people have heard this particular rant, so this will be my only
post, especially since the topic only has historical interest.

Thanks for your time,

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