Fast path vs. Interleave mode to reduce latency?
In DSL, Fast path vs. Interleave is an error correction scheme. if the error rate creeps up the CO/DSLAM may automatically impose Interleave mode to cope with that. Interleave helps resolve errors on longer loops and noisy lines. It rearranges bits before they are transmitted so that errors can be detected and possibly corrected. This Interleave process introduces a few ms delay (10-20ms) compared to Fast path, that may be an issue for gaming. Both the CO and CPE have to use the same setting, it may be the default used by your CO, or they may be using an automated sync optimization scheme.
Interleave mode may be imposed automatically by the condition of your line (high error rates, low upstream SNR), software optimizations by your provider to improve DSL stability, or by hardware/firmware upgrades at the DSLAM.
How to change from Interleave to Fast path to reduce latency:
- if your line syncs better than the speed you are provisioned for, it usually syncs using fastpath
- if there are no errors on the line, and no recent/frequent reboots the automated system may switch you to fast path from interleave mode.
- In some cases technical support may able to manually make changes to customers' sync profile to set either Fast path or Interleave mode.