Dynamic Line Management (DLM)
From EDPnet Wiki
What is DLM?
DLM (Dynamic Line Management) is a process allowing VDSL2 lines to benefit from higher bit rates (40 Mbps or 50 Mbps) than expected according to the provisioning rules based on loop length and attenuation, without significantly increasing the risk for transmission errors or instabilities.
What lines can benefit from DLM?
All VDSL2 lines with a profile of 30 Mbps.
How to get up to 50 Mbps?
DLM will be activated on the line if it satisfies the DLM eligibility rules and it is a completely automated process on which edpnet has no influence.
After some monitoring period at 30 Mbps (typically 1 week) the DLM tool will evaluate the line quality, stability and performances. The result of the evaluation could be that the line is expected to be able to support a higher bit rate than 30Mbps without giving up on transmission quality and stability. In that case the line will be reconfigured automatically at a higher bit rate (e.g. 40 Mbps or 50 Mbps).
Shortly after the line reconfiguration (typically 1 day) the DLM process will evaluate again the line quality, stability and performance. If the evaluation shows that the line quality, stability and performance are good, the line will remain as it is and a new evaluation will be planned. As long as line quality remains good, the line will not be reconfigured and new evaluation will be planned. When no configuration changes occur, the delay between two evaluations may increase.
There is no guarantee that the new improved speed once awarded by the DLM process on a VDSL2 line will always remain: if the line spectrum would change, in case for example of cross talk or interferences impacting neighbouring lines, the DLM process could decide to bring the line back to its initial line profile.
DLM will never downgrade a line to a profile lower than the provisioning profile.