Arista Networks, Broadcom, Intel, Molex, and AOI have announced formation of the 4x400G Multi-Source Agreement (MSA). The group plans to develop specifications for a 1.6-Tbps pluggable optical transceiver operating at 100 Gbps per lane. The resulting transceiver will be based on the OSFP-XD form factor.
The 4x400G MSA is a steppingstone towards establishing OSFP-XD as a viable option for high-speed chip I/O, beginning with 51.2-Tbps switch chips (see "New OSFP-XD form factor could challenge co-packaged optics"). The MSA group members note that the 100G Lambda optical interface standards that they will leverage support reaches up to 10 km on single-mode fiber and are in use today in 400G FR4 and 2x400G FR4 modules. Development of 4x400G optical transceivers therefore should be relatively straightforward, they feel, leading the members to anticipate that optical modules based on their upcoming specifications could see initial deployments as soon as 2023.
The group also suggests that their work could lead to 4x400G LR4 optical modules fully interoperable with 400G LR4 and 2x400G LR4 modules.
"Compatibility with the installed base of 100G Lambda optics is a key requirement for large customers to adopt the OSFP-XD high-density optics module form factor," said Andreas Bechtolsheim, CDO at Arista Networks. "The new 4x400G MSA will enable a multi-sourced ecosystem for 1.6T optics with 100G Lambda speed."
The four founding members of the MSA are recruiting contributor members. More information on the 4x400G MSA can be found on the group’s website.
A limited window for 4x400G transceivers?
In a research note, analysts at LightCounting speculate that Amazon encouraged the formation of the group so as to have a 1.6-Tbps option faster than would be the case if the hyperscaler had to wait for the development of 200G optical lanes. The market research firm notes that Marvell plans to make a 200G DSP available no earlier than 2023 that would have to run through a year of qualification.
That said, once that qualification process completes and transceivers based on them appear, the market window for 4x400G will begin to close. So the “sweet spot” for 4x400G modules will be 2023 to 2024, LightCounting estimates. Subsequent 8x200G based on 100G electrical lanes will have a similar two-year ramp before the development of 200G SerDes enables optical transceivers based on 200G electrical and optical lanes to reach the field around 2027, the analysts expect.
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Stephen Hardy | Editorial Director and Associate Publisher, Lightwave
Stephen Hardy is editorial director and associate publisher of Lightwave and Broadband Technology Report, part of the Lighting & Technology Group at Endeavor Business Media. Stephen is responsible for establishing and executing editorial strategy across the both brands’ websites, email newsletters, events, and other information products. He has covered the fiber-optics space for more than 20 years, and communications and technology for more than 35 years. During his tenure, Lightwave has received awards from Folio: and the American Society of Business Press Editors (ASBPE) for editorial excellence. Prior to joining Lightwave in 1997, Stephen worked for Telecommunications magazine and the Journal of Electronic Defense.
Stephen has moderated panels at numerous events, including the Optica Executive Forum, ECOC, and SCTE Cable-Tec Expo. He also is program director for the Lightwave Innovation Reviews and the Diamond Technology Reviews.
He has written numerous articles in all aspects of optical communications and fiber-optic networks, including fiber to the home (FTTH), PON, optical components, DWDM, fiber cables, packet optical transport, optical transceivers, lasers, fiber optic testing, and more.
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