Result: standard mapping
How many DS2s are in an OC-1?
An OC-1 carries 7 DS2s, per Telcordia GR-253.
7
DS2s in an OC-1
Working
OC-1 (STS-1) → 7 × DS2
- 7 × DS2 in each OC-1 (STS-1) Telcordia GR-253Seven VT groups, one VT6 (DS2) each.
- 7 DS2s
Leftover capacity
7.656 Mbit/s of each OC-1 line rate (51.840 Mbit/s) sits outside 7 × 6.312 Mbit/s of DS2 line rate (44.184 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 8.21, which floors to 8 DS2s by bit rate only. The standard mapping is 7. Use the mapping.