How broadband works: Difference between revisions
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Some lines are very stable, having the same characteristics all of the time. These lines need very low margins. However some lines vary a lot, and this can be over a daily cycle depending on temperature or weather conditions which affect the performance of the line and levels of interference affecting the line. Such lines need higher margins. |
Some lines are very stable, having the same characteristics all of the time. These lines need very low margins. However some lines vary a lot, and this can be over a daily cycle depending on temperature or weather conditions which affect the performance of the line and levels of interference affecting the line. Such lines need higher margins. |
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With BT ADSL and FTTC circuits there is an automatic system to establish that a line is re-syncing a lot and adjust the margin to be higher in future. This is called Dynamic Line Management (DLM) and runs all of the time. It can take a few days for a new line to get the right margins for stable operation when first install, but in practice it is rarely more than the first few hours. |
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The margin on TalkTalk lines can be adjusted manually by staff and customers. |
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==Interleaving== |
==Interleaving== |
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