Result: standard mapping
How many DS1s are in an ODU0?
An ODU0 carries 336 DS1s, per ITU-T G.709 and ITU-T G.707. This path maps STM-4 into ODU0 as a client, then follows that client's tributaries.
336
DS1s in an ODU0
Working
ODU0 → 1 × STM-4 → 4 × STM-1 → 84 × DS1
- 1 × STM-4 in each ODU0 ITU-T G.709Client mappingCBR STM-4 mapped into OPU0.
- 4 × STM-1 in each STM-4 ITU-T G.7074 × STM-1.
- 84 × DS1 in each STM-1 ITU-T G.70784 VC-11 tributaries: 3 TUG-3 × 7 TUG-2 × 4 TU-11.
- 1 STM-4
- 1 × 4 = 4 STM-1s
- 1 × 4 × 84 = 336 DS1s
Leftover capacity
725.376 Mbit/s of each ODU0 line rate (1.244160 Gbit/s) sits outside 336 × 1.544 Mbit/s of DS1 line rate (518.784 Mbit/s). That remainder is overhead, fixed stuff or justification. It is not another whole tributary.
By bit rate only
Dividing the line rates gives 805.8, which floors to 805 DS1s by bit rate only. The standard mapping is 336. Use the mapping.