Momentum Builds Around OpenZR+

By Eugene Park | Posted on December 9, 2019

Over the last few months, there has been increasing industry buzz around the standardization efforts taking place around OpenZR+. Widely considered the next logical step for providing an open, flexible and coherent solution in a small form factor pluggable module, OpenZR+ addresses not only hyperscale data center applications for higher-performance edge and regional interconnects, but also potential future carrier applications.

What exactly is OpenZR+?
OpenZR+ maintains the simple Ethernet-only host interface of 400ZR while adding support for enhanced capabilities that make it possible to develop a QSFP-DD or OSFP module designed to utilize OpenZR+, supporting reaches well beyond the 120km supported by 400ZR. As depicted in the image below, key features in OpenZR+ include:

  • Higher coding gain using oFEC from the OpenROADM standard, which extends the reach capability;
  • Multi-rate Ethernet, which enables the multiplexing of 100GbE and 200GbE clients over the line-side link, providing optimization options for the switch/router equipment to channelize the traffic over the transport link;
  • Adjustable 100G, 200G, 300G or 400G line-side transport links (using QPSK, 8QAM, or 16QAM modulation), which enables reach/capacity optimization over various fiber links; and
  • Higher dispersion tolerance.

Growing Industry Support
OpenZR+ has already been publicly supported by numerous industry leaders. At ECOC, Optical Connections Magazine published a contributed article on this new mode co-authored by Acacia, Fujitsu Optical Components America, Juniper Networks, Lumentum, and NTT Electronics America.

Also at the show, Acacia and NTT announced that they had successfully completed testing to demonstrate interoperability between coherent DSPs supporting OpenZR+ by exchanging test vectors. When asked about the significance of this announcement, Tom Williams, Acacia’s Vice President of Marketing, said “We believe that the availability of merchant DSP solutions supporting OpenZR+ will be a significant milestone by helping to expand the use cases for interoperable coherent pluggable modules in a QSFP-DD or OSFP form factor. OpenZR+ was designed to combine the focus on ethernet traffic of 400ZR, the performance of the OpenROADM specification, and multi-vendor interoperability in order to provide network operators with an operationally efficient solution for DCI applications with reaches beyond 120km.”

How to Participate
Multiple vendors are currently evaluating the next steps with OpenZR+, such as the creation of an OpenZR+ multi-source agreement (MSA). For more information on OpenZR+, including an historical look at how standardization efforts around 400ZR and OpenROADM led to this new mode, refer to this white paper from Acacia, “OpenZR+ Advances Coherent Interoperability.”

If you’re a vendor interested in OpenZR+ implementation details contact us.