Result: standard mapping
How many E1s are in an ODU1?
An ODU1 carries 1,008 E1s, per ITU-T G.709 and ITU-T G.707. This path maps STM-16 into ODU1 as a client, then follows that client's tributaries.
1,008
E1s in an ODU1
Working
ODU1 → 1 × STM-16 → 16 × STM-1 → 63 × E1
- 1 × STM-16 in each ODU1 ITU-T G.709Client mappingCBR STM-16 mapped into OPU1.
- 16 × STM-1 in each STM-16 ITU-T G.70716 × STM-1.
- 63 × E1 in each STM-1 ITU-T G.70763 VC-12 tributaries: 3 TUG-3 × 7 TUG-2 × 3 TU-12.
- 1 STM-16
- 1 × 16 = 16 STM-1s
- 1 × 16 × 63 = 1,008 E1s
Leftover capacity
434.391126 Mbit/s of each ODU1 line rate (2.498775126 Gbit/s) sits outside 1,008 × 2.048 Mbit/s of E1 line rate (2.064384 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 1,220.1, which floors to 1,220 E1s by bit rate only. The standard mapping is 1,008. Use the mapping.