40GBASE-FR Application Overview


40GBASE-FR: 40 Gb/s serial transmission at 1310 nm and 1547.5 nm over 2 single‑mode optical fibers, with reach up to at least 2 km

40GBASE-FR supports extra-long wavelength serial transmission over duplex (2‑fiber) single‑mode optical fiber cabling. The application’s nominal symbol rate is 41.25 GBd per lane and the supported distance varies according to the type of single‑mode cable used. Network equipment interface connections include a duplex optical fiber connector and a standard socket into which physical (PHY) layer transceiver modules may be plugged.

  • Connector type: LC
  • Transceiver module: CFP
  • Defined in clause 89 of the IEEE 802.3 Standard for Ethernet
  • Initially published as IEEE Std 802.3bg™: Physical Layer and Management Parameters for Serial 40 Gb/s Ethernet Operation Over Single‑Mode Fiber in 2011

Optical Fiber Cabling (Channel) Characteristics:

Parameter OS1a Indoor/Outdoor OS2
Operating wavelengths: 1310 nm1 and 1547.5 nm
Specification wavelength: 1550 nm
Insertion loss (max): 4.0 dB
Cabled fiber attenuation (max): 1.0 dB/km 0.5 dB/km 0.4 dB/km
Operating range2: 2 m to 1 km3 2 m to 2 km 2 m to 2 km
1 Receive capability only at 1310 nm.
2 Maximum operating ranges are calculated using a 3.0 dB connection and splice loss allocation.
3 Operating range for cabled fibers having more than 0.5 dB/km attenuation is not specified by IEEE 802.3. This calculation is provided for information only.

Key Application Capabilities:

  • Defines a 40 Gb/s PHY for operation over at least 2 km of SMF
  • Preserves the Ethernet frame format utilizing the Ethernet MAC
  • Preserves minimum and maximum FrameSize of current 802.3 Standard for Ethernet
  • Supports a BER of better than or equal to 10-12 at the MAC/PLS service interface
  • Uses only existing electrical and logical interfaces from IEEE Std 802.3 as modified by IEEE P802.3ba
  • Provides optical compatibility with existing carrier 40 Gb/s client interfaces (OTU3/STM‑256/OC‑768/40G POS)

Back to TIA FOTC IEEE 802.3 Single-mode Optical Fiber Ethernet Standards Explorer