Kitz Forum
Broadband Related => Router Monitoring Software => Topic started by: aesmith on February 03, 2016, 03:34:05 PM
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Hi,
A quick question on the Bit Swaps per tone graph. Do the lines indicate the tones from which bits have been removed, or the tone to which they've been added. I'm trying to think through whether I can pick clues about which frequencies are affecting our line.
Thanks, Tony S
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The bitswaps per tone graph looks at each tone and compares its number of bits with the value in the previous sample. Any changes (whether up or down) are counted as bitswaps. So in reality every true bitswap is counted twice, once for the losing tone and once again for the receiving tone. To be frank, I'm not sure that it's very useful in its present form - my idea at the time was to give a picture of the shape of bitswapping over the range, not actual values.
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Cheers, so would I be better looking at the bits per tone snapshots, to see where "holes" appear?
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Personally, I focus on the total bitswaps per minute graph across all the tones to give an indication of lines that need it & those that don't.
Almost all connections need DS bitswapping to some extent & some need it more than others.
With VDSL2, if a connection also needs a lot of US bitswapping, it is often an indication of either a very noisy connection or that a potential physical cabling issue is brewing.
I have attached a graph showing 24 hours worth of bitswapping from my own 1100m long VDSL2 connection as an example.
Just for info, DS bitswapping per minute before the 2013 HG612 modem firmware update was at a much lower lower level (see the other attached graph).
Increased DS bitswapping was a definite improvement, certainly for my connection, as it actually reduced error counts & improved stability.