Result: standard mapping
How many E1s are in an OC-192?
An OC-192 carries 4,032 E1s, per Telcordia GR-253.
4,032
E1s in an OC-192
Working
OC-192 → 192 × OC-1 (STS-1) → 21 × E1
- 192 × OC-1 (STS-1) in each OC-192 Telcordia GR-253192 × OC-1 (STS-1). Channelized OC-192 is 192 STS-1s.
- 21 × E1 in each OC-1 (STS-1) Telcordia GR-253Seven VT groups × three VT2 (E1).
- 192 OC-1s
- 192 × 21 = 4,032 E1s
Leftover capacity
1.695744 Gbit/s of each OC-192 line rate (9.953280 Gbit/s) sits outside 4,032 × 2.048 Mbit/s of E1 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 4,860, which floors to 4,860 E1s by bit rate only. The standard mapping is 4,032. Use the mapping.