Result: standard mapping
How many DS0s are in an OC-192?
An OC-192 carries 129,024 DS0s, per Telcordia GR-253 and ANSI T1.107.
129,024
DS0s in an OC-192
Working
OC-192 → 192 × OC-1 (STS-1) → 28 × DS1 → 24 × DS0
- 192 × OC-1 (STS-1) in each OC-192 Telcordia GR-253192 × OC-1 (STS-1). Channelized OC-192 is 192 STS-1s.
- 28 × DS1 in each OC-1 (STS-1) Telcordia GR-253Seven VT groups × four VT1.5 (DS1).
- 24 × DS0 in each DS1 ANSI T1.10724 payload timeslots. The framing bit adds 8 kbit/s and brings the line rate to 1.544 Mbit/s.
- 192 OC-1s
- 192 × 28 = 5,376 DS1s
- 192 × 28 × 24 = 129,024 DS0s
Leftover capacity
1.695744 Gbit/s of each OC-192 line rate (9.953280 Gbit/s) sits outside 129,024 × 64 kbit/s of DS0 line rate (8.257536 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 155,520, which floors to 155,520 DS0s by bit rate only. The standard mapping is 129,024. Use the mapping.