Paul, Unfortunately, the presentation I have privately from a friend hasn't yet been published, which is a pain for citation.
A1 Telekom's field trial in Austria, covering 500 premises, was interesting. A1 is a happy customer of VDSL2 plus vectoring - but on customer copper, the performance at 800 meters converged to about 25 Mbps. Which is in line with what you mentioned about "ADSL2++++" Within the 100m to 800m range, what I found interesting in the raw data was that on the same copper plant, VDSL2 + vectoring has a greater top-to-bottom variation than ADSL2+ - bottom speeds of the two technologies are about the same beyond 300 meters. I wish A1 Telekom would publish its data so I can do a proper public analysis of it! Cheers, Richard Chirgwin On 25/04/13 2:16 PM, Paul Brooks wrote: > While I'm definitely not a fan of the latest proposal, I think it is > important that > rebuttal should also be based on facts, and that un-challenged assertions are > unhelpful no matter what side you're on. > > Frank - you've done a great job of distilling out many of the issues, and I > don't want > to detract from those, but there is one item that is more urban myth than > fact... > > To that point.... > > > On 23/04/2013 6:49 PM, Frank O'Connor wrote: >> 6. Probably won't scale as well as Turnbull estimates, and the signal >> attenuation and drop-off is much higher than he estimates. Only those living >> right on top of the cabinets (read ... just outside their door) will get >> 40-50Mbs ... the other 80 to 100 or so clients per cabinet will get from >> there down to 5 Mbs ... with I estimate a mean value of about 10-15 Mbs. > Assuming they build the 60,000 cabinets, and shorten all the copper lines to > being no > more than 800 metres long, then real-world measurements show they should > achieve > reasonable speeds over those distances. Signal attenuation and drop-off isn't > dramatically more than ADSL2+, as VDSL2 is just ADSL2++++, extended to higher > frequencies. > At a minimum, on maximum length 800 metre lines VDSL2 will deliver at least > as much as > ADSL2+ would on 800m lines, and usually considerably more. > > While these are AlcatelLucent test results, and so subject to the usual vendor > caution, they appear to be based on tests on real-world copper networks. > > http://www2.alcatel-lucent.com/techzine/vdsl2-vectoring-in-a-multi-operator-environment-separating-fact-from-fiction/ > shows that normal (non-vectored) VDSL2 at 800m should deliver between 28 - 38 > Mbps, > and vectoring should raise this to 50 Mbps, at 800m. > > http://www2.alcatel-lucent.com/techzine/vdsl2-vectoring-delivers-on-its-promise/ > shows > vectored VDSL2 delivers at least 40, and for latest tech around 60 - 80 Mbps > at 800 > metres. Caution is that we don't know what gauge copper the various telcos had > installed and were tested over, good results might be due to better tech, or > a telco > infrastructure with thicker wires. > > At the very least, everyone should get better than ADSL2+ at 800 metres, > which is > around 18 - 20 Mbps. > > P. > _______________________________________________ > Link mailing list > [email protected] > http://mailman.anu.edu.au/mailman/listinfo/link > _______________________________________________ Link mailing list [email protected] http://mailman.anu.edu.au/mailman/listinfo/link
