[LINK] tRe: NBN white-elephant-to-be ...
Richard Chirgwin
rchirgwin at ozemail.com.au
Thu Aug 26 09:34:51 AEST 2010
Marghanita da Cruz wrote:
> Roger Clarke wrote:
>
>> When I saw the viral letter ('$60bn Fiasco'), I:
>> - wrote to someone who I knows more about broadband than I do
>>
> <snip>
>
>> Similarly, his faith in wireless is wildly optimistic. He does
>> acknowledge contention ratios, but nevertheless goes on to intimate
>> that 100Mbps performance could be a realistic customer expectation.
>> The spectrum required to deliver this to bandwidth hungry customers
>> in high-density urban areas just isn't available unless cell-sizes
>> are reduced to ridiculously small levels (a tower every few hundred
>> meters). Once again, he could do well to go back and study some basic
>> physics.
>> <snip>
>>
>
> Sorry Roger,
>
> Your correspondent sounds like a fibre optic junkie.
>
That's different from being a wireless junkie how, exactly?
> FWIW - Energy Australia is replacing its copper with
> Aluminium (for their electricity grid).
>
> Deploying a tower every few hundred metres isn't as
> difficult as deploying capiliaries of fibre terminated with
> something to convert from optical transmission to
> electricity, for either wireless or ethernet LAN (basic
> common sense).
>
Let's pick up cells of max size 500 metres, and ignore two side issues
(how much will 100,000 towers in Sydney cost, and will people tolerate
wireless towers everywhere?). Let's just stick to performance.
From page 399 of "3G Evolution: HSPA and LTE for Mobile Broadband",
(Dahlman, Parkvall, Skold and Beming, Academic Press, ISBN
978-0-12-372533-2), there is a graph charting LTE capacity.
If the system is using 5 MHz radio channels, the performance at 500
metres from the base station is 20 Mbps; with 10 users, the per-user
budget is about 2 Mbps.
The charts for performance with 20 MHz radio channels are harder to
interpret, but the best total throughput of the entire radio channel is
about 110 Mbps - about 10 Mbps if there's ten users in the cell (my
interpretation of the chart given on page 404 of the same book).
So: let's assume that whether we're in the city or the country, we can
serve almost adequate bandwidth to ten users in one cell; that the total
capex of a base station (with three cells) is about $90,000. We get
90/30 or $3,000 capex per household. It's not so much cheaper than
pulling fibre.
RC
> In any event, the NBN in high density urban areas is a
> non-issue - the market meets demand.
>
> Linkers may also like to note this snippet from the
> 2010 Charles Todd Memorial Oration by
> NBN Co chief executive, Mike Quigley:
>
>> Paul Fletcher in his book Wired Brown Land wrote what you
>> see up on this slide:
>>
>> My fundamental argument is that we need to get the
>> market structure right first if we do that, the right
>> technology will follow.
>>
>> " .. a market structure in which there are multiple
>> providers of retail telephony and broadband services ? and
>> they all operate over the same network on equal terms. For
>> that to happen, none of them must own or control the
>> network. Instead, they must buy services from the owner of
>> the network? and in turn the network owner must be
>> restricted to selling services in the wholesale market
>> rather than the retail market.? (viii)
>>
>> I think Paul absolutely nailed it with these words,
>> arguing for a single national wholesale only provider.
>>
> <http://www.arnnet.com.au/article/357411/2010_charles_todd_memorial_oration_by_nbn_co_chief_executive_mike_quigley/?pp=2&rid=-100>
>
> Paul Fletcher now Liberal MP was
>
>> Paul Fletcher is Director, Corporate and. Regulatory Affairs at Optus. In this role he has responsibility for the internal legal function; regulatory issues ...
>> www.atug.com.au/bio/BioPaulFletcher.pdf - Similar
>>
>
> Marghanita
>
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