Quantity is how many containers you have. The result is how many tributaries fit, the path, and the leftover line rate. The choices stay in the URL, so you can share them.

Result: standard mapping

How many STM-1s are in an ODU3?

An ODU3 carries 256 STM-1s, per ITU-T G.709 and ITU-T G.707. This path maps STM-256 into ODU3 as a client, then follows that client's tributaries.

256

STM-1s in an ODU3

Working

ODU3 → 1 × STM-256 → 256 × STM-1

1 × STM-256 in each ODU3 ITU-T G.709Client mappingCBR STM-256 mapped into OPU3.
256 × STM-1 in each STM-256 ITU-T G.707256 × STM-1.

1 STM-256
1 × 256 = 256 STM-1s

Leftover capacity

506.098983 Mbit/s of each ODU3 line rate (40.319218983 Gbit/s) sits outside 256 × 155.520 Mbit/s of STM-1 line rate (39.813120 Gbit/s). That remainder is overhead, fixed stuff or justification. It is not another whole tributary.

By bit rate only

Dividing the line rates gives 259.25, which floors to 259 STM-1s by bit rate only. The standard mapping is 256. Use the mapping.

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