Result: standard mapping
How many E0s are in an OC-48?
An OC-48 carries 30,240 E0s, per Telcordia GR-253 and ITU-T G.704.
30,240
E0s in an OC-48
Working
OC-48 → 48 × OC-1 (STS-1) → 21 × E1 → 30 × E0
- 48 × OC-1 (STS-1) in each OC-48 Telcordia GR-25348 × OC-1 (STS-1). Channelized OC-48 is 48 STS-1s.
- 21 × E1 in each OC-1 (STS-1) Telcordia GR-253Seven VT groups × three VT2 (E1).
- 30 × E0 in each E1 ITU-T G.70430 voice channels in 32 timeslots. TS0 is framing and TS16 is channel-associated signalling.
- 48 OC-1s
- 48 × 21 = 1,008 E1s
- 48 × 21 × 30 = 30,240 E0s
Leftover capacity
552.960 Mbit/s of each OC-48 line rate (2.488320 Gbit/s) sits outside 30,240 × 64 kbit/s of E0 line rate (1.935360 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 38,880, which floors to 38,880 E0s by bit rate only. The standard mapping is 30,240. Use the mapping.