ITU Wavelength Bands Range
| Band Name | Description (meaning) | Wavelength Range (nm) |
| O-band | Original | 1260 ~ 1360nm |
| E-band | Extended | 1360 ~ 1460nm |
| S-band | Short | 1460 ~ 1530nm |
| C-band | Conventional | 1530 ~ 1565nm |
| L-band | Long | 1565 ~ 1625nm |
| U-band | Ultra-long | 1625 ~ 1675nm |