| Band Name | Wavelengths | Description |
| O-band | 1260 – 1360 nm | Original band, PON upstream |
| E-band | 1360 – 1460 nm | Water peak band |
| S-band | 1460 – 1530 nm | PON downstream |
| C-band | 1530 – 1565 nm | Lowest attenuation, original DWDM band, compatible with fiber amplifiers, CATV |
| L-band | 1565 – 1625 nm | Low attenuation, expanded DWDM band |
| U-band | 1625 – 1675 nm | Ultra-long wavelength |
O-Band
PRO
• Lowest fiber dispersion -no DCM for 20km PMDs*
• Existing cooled 100GLR4 lasers and EMLs
• Existing high power uncooled 25G lasers
CON
• High fiber insertion loss
• Limited fiber spectrum – 10G WDM coexistence and zero dispersion zone
• SOA preamp has high NF
• SOA booster has limited Psat
S-Band
PRO
• Low fiber insertion loss
• Moderate fiber dispersion — no DCM for 10km PMDs
• Open fiber spectrum — no coexistence objectives
CON
• DCM required for 20km PMDs
• No existing 25G sources
• SOA preamp has high NF
• SOA booster has limited Psat
C-Band
PRO
• Low fiber insertion loss
• Moderate fiber dispersion — no DCM for 10km PMDs
• High power booster EDFAs
• Low-NF preamp EDFAs
CON
• DCM required for 20km PMDs
• 10G WDM coexistence prevents use of 1560- 1600nm
L-Band
PRO
• Low fiber insertion loss
• High power booster EDFAs
• Low-NF preamp EDFAs
CON
• High fiber dispersion — DCM required for all PMDs
• Limited fiber spectrum – 10G WDM coexistence and OTDR band
• Lower laser efficiency
