high latency ds3 issue on unloaded line

Jay Hennigan jay at west.net
Fri Sep 26 14:20:24 CDT 2008

John Lee wrote:
> Mike,
> Your latencies which suddenly appear for several hours and then go away and do this on a regular basis  sounds like a layer 2, facility switching issue. As you indicated " the problem comes on during the day and then lets up late in the evening" sounds like the under lying facility is being switched back around the "long side" of the SONET ring or other facility. Some carrier facilities are scheduled for "one path or direction" say during the day that are supposed to be for lower latency time periods for interactive work and then switch for a lower cost, higher latency path in the evening when computer to computer backups do not care. If you can plot the times the issues start and end and that these occur daily during the week and not on weekends etc that would be a strong indicator.

For 1000 ms latencies, that would be a VERY long "long side".  I think 
there is something else going on here.

Jay Hennigan - CCIE #7880 - Network Engineering - jay at impulse.net
Impulse Internet Service  -  http://www.impulse.net/
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