IEEE P802.3cw 400 Gb/s over DWDM Systems Task Force Update


IEEE Std 802.3cw™: “Physical Layers and Management Parameters for 400 Gb/s Operation over DWDM systems” is currently under development by the IEEE P802.3cw 400 Gb/s over DWDM Systems Task Force and anticipated to publish in September, 2024.

Summary: Mobile backhaul applications are demanding increased bandwidth capacity at reaches beyond 40 km. This amendment will define one Physical Layer (PHY) specification and management parameters for 400 Gb/s operation over a DWDM system.

400GBASE-ZR: 400 Gb/s dense wavelength-division multiplexed (DWDM) DP‑16QAM serial transmission over 2 single‑mode optical fibers, with reach up to at least 80 km


The Project Objectives, approved on November 15, 2018, are as follows:

Non-Rate Specific:

  • Supports full-duplex operation only
  • Preserves the Ethernet frame format utilizing the Ethernet MAC
  • Preserves minimum and maximum FrameSize of current IEEE 802.3 standard
  • Provides appropriate support for optical transport networks (OTNs)

400 Gb/s Related:

  • Supports a MAC data rate of 400 Gb/s
  • Supports a BER of better than or equal to 10-13 at the MAC/PLS service interface (or the frame loss ratio equivalent)
  • Provides a physical layer specification supporting 400 Gb/s operation on a single wavelength capable of at least 80 km over a DWDM SMF system

The IEEE 802.3 Beyond 10 km Optical PHYs Study Group Call-For-Interest Consensus Presentation can be found here.

Additional information on IEEE 802.3 Ethernet Working Group activities may be found here.