BT like most entrenched quasi-monopolists is run by idiots — and no change will permanently alter institutions.
Not BT, just their community boards:
Does turning router off every night affect speed?
*The recommendation is that your router remains connected 24/7 however there are many who switch off before going to bed The problem would be if you were to switch back on and then off quickly or the router reset and you switched it of shortly after as the exchange might see this as a noise problem and drop your speed. *
*I would advise that you leave the HomeHub on 24/7 this could be the cause. DLM in the exchange will change your SNR and speed accordingly, I would give it 10 days to see a notable increase.
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*Dynamic Line Management (DLM) is a process which continously monitors your line to ensure that a stable connection is being maintained.
This works by data being sent to the DSLAM every time you connect to the Internet, including line data and any errors on the phone line.
The information is collated by the Data Collector which in turn sends it to the Dynamic Line Management system.
Should the DLM detect an issue on the line it will adjust SNR and Interleaving settings or decrease your connection (sychronisation) speed to a level which will provide you with a stable connection.
If on the contrary your connection proves stable at a higher sychronisation speed, DLM will increase your profile to operate at this level.
It’s important to note that your connection must remained sychronised at the higher rate for 3 days before DLM will update your BRAS profile.
If any changes are made, DLM sends the information via the flow stream to NCAS. NCAS then reports to the DSLAM which then makes the relevant changes to the individual users line card.‘’*
Disconnection due to Turning off Router?!
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The reason that it is recommended to leave your router on 24/7 is that turning it off and on can be interpreted by the DLM (Dynamic Line Management) as a possible fault on the line. If it does, the DLM may lower your speeds to a speed that it has deemed the “faulty” line can support.
See this link about DLM
http://www.thinkbroadband.com/files/broadband-max-myths-and-legends.pdf*
Other sources:
United Kingdom internal phone systems
This “degradation” appears as a reduction in the signal to noise ratio (SNR), and as CRC errors counted up by the modem and in some cases cause disconnections, or prevents the end user getting the speed their line should be capable of. As we move to faster speeds and to "rate adaptive” services where the ADSL goes as fast as the line allows it, the dear old ring wire will slow down our connections.
Broadband SNR Margin Tweak ( Guide )
The exchange equipment attempts to set the downlink connection speed such that there is a sufficiently high SNR margin to guarantee a reliable connection (without regular drops and/or an unacceptable number of errors). This specific margin that the exchange tries to achieve is called the target SNR margin. The higher the target SNR margin, the lower your connection speed.
When your broadband service is first switched on, the target SNR margin is set by the BT exchange equipment at 6 dB. On a good line, BT generally considers that a 6 dB SNR margin is appropriate to maintain a connection without a significant number of drops or errors. The corresponding target margin for TalkTalk equipment is 9 dB.
As part of the Digital Line Management process, the exchange equipment continuously monitors your broadband connection, for example recording the number of times that it drops and the number of errors it suffers. If the line experiences any issues (such as bursts of errors at a particular time), the exchange equipment can increase the target SNR margin – usually in steps of 3 dB. This action – aimed at stabilising the line – reduces the connection speed.