Kitz Forum
Broadband Related => Broadband Technology => Topic started by: Weaver on October 23, 2009, 04:31:13 PM
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Does anyone have any links to articles, reliable numbers relating to the subject of DSL performance limits versus physical line lengths in the UK, assuming various choices for common species of BT copper?
Is there a lot of v outdated material on the web on this?
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OK... what information are you looking for in total?
You have serveral posts all over and I feel it might be better if you place all your questions in one post. ;)
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> you place all your questions in one post. ;)
Understood. I specifically didn't want to mix things up as people may be able to contribute to one topic and not be interested in others.
There are a lot of useful resources around on the web which offer to calculate likely performance based on attenuation figures. But my question is: are there some numbers we can use as a benchmark to compare different physical lines' voltage drop (only), to translate line length into numbers you might expect to see in a (admittedly non-existent) DSL modem's attenuation figure?
The aim is to get an idea if the actual copper is thin/thick good/bad as compared with other lines, compare true line length of different lines while trying as far as possible to treat issues of noise separately. Or alternatively to answer the question "do I have a physically long/bad line?" itself as opposed to a line with decent copper, but in a bath of noise/crosstalk.
Do we see lines that have very different attenuation figures from what we expect knowing the true line length?
[Things that cloud the issue: we have to understand that different sync rates/protocols will use higher frequencies or not, noise is variable, and signals propagate better/worse at different frequencies and these frequencies may be avoided/exploited to a different extent.]