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Is there published documentation on best-case and worst-case latency added by SONET ADM equipment?

Specifically I'm looking for the latency I could expect to be added to an OC-3 piped through these pieces of gear:

  • Fujitsu FlashWave 4500 MSPP
  • Cienna 1600 DWDM
  • Nortel OC-48 Classic
  • Nortel OC-192 Transparent

Case studies or white papers on expected latency in as the bits get framed are also useful.

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up vote 3 down vote accepted

Given a base STM-1 frame is 2430 bits (@155Mbit, 125usec) you can work latencies out from that.

Worst case should be two frame intervals of latency (one to read in, the second for the timeslot in the out flow), plus perhaps a little (< 5% at a guess) overhead, somthing like 0.3msec.

As latency from distance so overwhelms this the general consensus seems to be "don't worry".

Oh, and thanks to Wikipedia for the basic numbers, my SONET book is at the office.

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Some day I will remember to reference serialization delay in my brain. Thanks. Any idea where to get more precise numbers for the "5%"? – James Cape Jun 26 '09 at 16:09

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