800G is becoming a talking point and it is one topic that can mean different things to different people.

The main thrust today is development of 800G class pluggable modules. We are seeing the first 800G modules, both QSFP-DD800 and OSFP-800 appearing in the market. Although they carry an 800G tag they are really focused in delivering high density breakout for 400Gb and 100Gb Ethernet as 2 x 400Gb or 8 x 100G in the same space as you used to get a 400Gb port. These 800G modules are part evolution and part revolution, in that they leverage existing form factors and established Ethernet rates and interfaces, but require the very latest generation of 100G electrical SERDES and the latest module management – CMIS 5.

The 800G Ethernet Pipe

With Ethernet itself, we have seen the first generation of 800G via the 800G Ethernet Consortium.  It builds on the existing IEEE standard 802.3 at 400G to ‘glue’ together two 400G pipes to deliver an 800G link.  This allows efficient reuse of many of the current logic blocks built into 400G class ICs, such as switch silicon giving a relatively quick path to 800G Ethernet.

Of course, it is important to realize that this is a specification rather than a standard. The authority for Ethernet standards, the IEEE, has work underway in the 802.3df working group–and industry experts, including VIAVI, are delivering contributions on what can underpin 800G and 1.6Tb Ethernet. The IEEE 802.3 develops robust standards which provide the foundation for the success of our multi-vendor ecosystem.  This detailed work will take time, so we may see the utilization of the 800G ETC specifications in the near term and the IEEE may choose to leverage this early work to accelerate things.

800G is a Reality Today

We already see a busy ecosystem of chips, modules and systems coming together with lead customers needing 800G class products. VIAVI has been actively involved in the ecosystem with our ONT range, and we have already been part of many successful product demos and interop.  However, the technology remains challenging – especially the themes around 100G electrical lanes and the far more advanced module management using CMIS 5.0. Many challenges lie ahead from technology to economics and production scaling, and all need to be addressed at the earliest stage to allow successful products to be brought to market on time and on cost.

ONT 800G FLEX XPM Module

Early IC Development to Production and Deployment

Here is an ONT 800G together with 100G electrical adapters doing some live Ethernet traffic testing on a prototype 800G module more than 2 years ago!  We have been helping accelerate development since the very beginning of each technology, from 2Mb/s E1 to 800G Ethernet today.  From the earliest IC and SERDES evaluations to wide scale production and deployment, VIAVI offers the right solutions to accelerate your product lifecycle.

ONT Chassis with 100G Adapters

If you have any questions around 800G, please contact your local VIAVI sales representative, or visit our website, www.viavisolutions.com, to find out more about developing and validating 800G technology.

About The Author

Paul Brooks is technology lead for Optical Transport in the VIAVI Lab and Production business unit. After a career in the Royal Navy as a weapons officer he spent time in a variety of roles with the communications test and measurement industry with a particular interest in enabling the high-speed Ethernet ecosystem. He holds a PhD in opto-electronics from the University of Southampton and lives in Southern Germany.

Close