100GBASE-SR4 Application Overview


100GBASE‑SR4: 100 Gb/s parallel transmission at 850 nm over 8 multimode optical fibers, with reach up to at least 100 m

100GBASE‑SR4 supports short wavelength parallel transmission over four lanes (8‑fibers) of multimode optical fiber cabling. The application’s nominal symbol rate is 25.78125 GBd per lane and the supported distance varies according to the type of multimode cable used. Network equipment interface connections include a multi-fiber push on (MPO) connector and standard sockets into which a physical (PHY) layer transceiver module may be plugged.

  • Connector type: MPO/MTP
  • Transceiver module: QSFP28, CFP2, CFP4, CPAK
  • Defined in clause 95 of the IEEE 802.3 Standard for Ethernet
  • Initially published as IEEE Std 802.3bm™: Physical Layer Specifications and Management Parameters for 40 Gb/s and 100 Gb/s Operation over Fiber Optic Cables in 2015

Optical Fiber Cabling (Channel) Characteristics:

Parameter OM3 OM4 OM5 Unit
Operating wavelength: 850 nm
Modal bandwidth (min): 2,000 4,700 MHz∙km
Operating range: 0.5 to 70 0.5 to 100 m
Insertion loss (max): 1.8 1.9 dB
Cabling skew (max): 79 ns
Cabling skew variation: 2.4 ns

Key Application Capabilities:

  • Defines a four-lane 100 Gb/s PHY for operation up to at least 100 m of MMF
  • Supports full-duplex operation only
  • Preserves the Ethernet frame format utilizing the Ethernet MAC
  • Preserves minimum and maximum FrameSize of current 802.3 Standard for Ethernet
  • Provides appropriate support for optical transport networks (OTNs)
  • Supports a BER of better than or equal to 10-12 at the MAC/PLS service interface
  • Supports optional Energy-Efficient Ethernet operation

Related Applications:

The IEEE P802.3bm Task Force also specified the following Ethernet application:

Application    Operating    Wavelength Media Operating Range1
40GBASE-ER4 four WDM2 Single-mode up to 40 km3
1 Supported distance varies according to the type of optical fiber cable used.
2 1271 nm, 1291 nm, 1311 nm, and 1331 nm
3 Links longer than 30 km for the same link power budget are considered engineered links and must not exceed specified insertion loss.

Back to TIA FOTC IEEE 802.3 Multimode Optical Fiber Ethernet Standards Explorer