Result: standard mapping
How many DS2s are in an OC-12?
An OC-12 carries 84 DS2s, per Telcordia GR-253.
84
DS2s in an OC-12
Working
OC-12 → 12 × OC-1 (STS-1) → 7 × DS2
- 12 × OC-1 (STS-1) in each OC-12 Telcordia GR-25312 × OC-1 (STS-1). Channelized OC-12 is 12 STS-1s.
- 7 × DS2 in each OC-1 (STS-1) Telcordia GR-253Seven VT groups, one VT6 (DS2) each.
- 12 OC-1s
- 12 × 7 = 84 DS2s
Leftover capacity
91.872 Mbit/s of each OC-12 line rate (622.080 Mbit/s) sits outside 84 × 6.312 Mbit/s of DS2 line rate (530.208 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 98.55, which floors to 98 DS2s by bit rate only. The standard mapping is 84. Use the mapping.