Result: standard mapping
How many DS3s are in an ODU1?
An ODU1 carries 48 DS3s, per ITU-T G.709 and ITU-T G.707. This path maps STM-16 into ODU1 as a client, then follows that client's tributaries.
48
DS3s in an ODU1
Working
ODU1 → 1 × STM-16 → 16 × STM-1 → 3 × DS3
- 1 × STM-16 in each ODU1 ITU-T G.709Client mappingCBR STM-16 mapped into OPU1.
- 16 × STM-1 in each STM-16 ITU-T G.70716 × STM-1.
- 3 × DS3 in each STM-1 ITU-T G.707Three VC-3s, each able to carry a DS3.
- 1 STM-16
- 1 × 16 = 16 STM-1s
- 1 × 16 × 3 = 48 DS3s
Leftover capacity
351.447126 Mbit/s of each ODU1 line rate (2.498775126 Gbit/s) sits outside 48 × 44.736 Mbit/s of DS3 line rate (2.147328 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 55.85, which floors to 55 DS3s by bit rate only. The standard mapping is 48. Use the mapping.