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-256s are in an OTU4?
An OTU4 carries 2 STM-256s, per ITU-T G.709. This is a client mapping of STM-256 into ODU3.
2
STM-256s in an OTU4
Working
OTU4 → 1 × ODU4 → 2 × ODU3 → 1 × STM-256
- 1 × ODU4 in each OTU4 ITU-T G.709The OTU4 frame carries exactly one ODU4.
- 2 × ODU3 in each ODU4 ITU-T G.709Each ODU3 takes 31 of the 80 ODU4 tributary slots, so 2 fit and 18 slots stay unused.
- 1 × STM-256 in each ODU3 ITU-T G.709Client mappingCBR STM-256 mapped into OPU3.
- 1 ODU4
- 1 × 2 = 2 ODU3s
- 1 × 2 × 1 = 2 STM-256s
Leftover capacity
32.183733568 Gbit/s of each OTU4 line rate (111.809973568 Gbit/s) sits outside 2 × 39.813120 Gbit/s of STM-256 line rate (79.626240 Gbit/s). That remainder is overhead, fixed stuff or justification. It is not another whole tributary.
Share this result. Pairing page