Result: standard mapping
How many E3s are in a STM-1?
A STM-1 carries 3 E3s, per ITU-T G.707.
3
E3s in a STM-1
Working
STM-1 → 3 × E3
- 3 × E3 in each STM-1 ITU-T G.707Three VC-3s, each carrying an E3.
- 3 E3s
Leftover capacity
52.416 Mbit/s of each STM-1 line rate (155.520 Mbit/s) sits outside 3 × 34.368 Mbit/s of E3 line rate (103.104 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 4.52, which floors to 4 E3s by bit rate only. The standard mapping is 3. Use the mapping.