Optical Networks Using 400ZRZR+ -800ZRZR+ Optical Plugs

During the evaluations of 400G ZR and ZR+ technology, vendor interoperability was also performed on 400G and 100G ports. The 400G links used DP-16QAM line coding, whereas the 100G employed DP-QPSK. All were at the 193.700 TH carriers frequency, with the FEC settings adjusted as appropriate according to OpenZR+ or Standard ZR parameters.
We assessed end-to-end link quality by running 10G IMIX traffic across each back-to-back connection and monitoring for packet loss, CRC framing errors, and stability of BGP sessions. The links came online, and control protocols converged without issue. This test shows that 400ZR/ZR+ modules are interoperable in mixed setups, from 100G (DP-QPSK) to 400G (DP-16QAM).

The results highlight 400ZR/ZR+ as a key technology for high-capacity, greater-distance connections and data center interconnects. A slight flexibility in running different line rates and FEC modes would allow the operator to adapt the optical interface to meet a specific need-whether it is optimized for efficiency on metro-to-long-haul links or simply for easy interconnection on short-reach connections in data centers.