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Coherent 400G 800G QSFP-DD OSFP OpenZR+ OpenROADM Optical Networking Pluggable Supply Chain

Pluggable Coherent in 2026: What's Shipping, What's Vaporware

800G ZR modules are announced. 1.6T is on the roadmap. Meanwhile, half the 400G ZR+ SKUs take 14 weeks to ship. Here's what's real in pluggable coherent today.

Rene Fichtmueller / 2026-05-07 / ~2 min read min read
LPO Linear Pluggable Optics 800G DSP Power Efficiency Data Center Optical Networking OIF SerDes Latency AI Networking Signal Integrity LRO Network Design

Linear Drive Optics — Killing the DSP to Save a Megawatt

Most modern high-speed DSP-based pluggable optical modules contain a DSP that re-clocks and reshapes the electrical signal. That DSP can consume a significant part of the module power budget. For

Rene Fichtmueller / 2026-04-29 / ~4 min read min read
AI GPU Cluster Optical Networking 400G 800G RoCEv2 RDMA Data Center InfiniBand Network Fabric H100 B200 LPO Machine Learning HPC

AI Fabrics Need Different Optics — GPU Clusters Are Not Normal Data Centers

Your data center runs web applications. Your procurement team buys optics for web application traffic. Then someone installs a GPU cluster, and the optics team discovers that AI fabric traffic

Rene Fichtmueller / 2026-04-28 / ~4 min read min read
Optical Networking CPO Co-Packaged Optics 800G Data Center QSFP-DD OSFP Pluggable Optics Silicon Photonics Thermal Management Hyperscale Power Efficiency 1.6T

CPO Won't Save You — Co-Packaged Optics and the Modularity Trade-Off

Co-Packaged Optics will cut power consumption in half. CPO will eliminate transceiver inventory headaches. CPO will redefine data center design. You have heard the pitch. The pitch skips the parts

Rene Fichtmueller / 2026-04-27 / ~3 min read min read
Optical Networking 800G 400G Deployment Data Center Optical Transceiver OSFP QSFP-DD PAM4 Network Design TCO Fiber Infrastructure

800G: The Upgrade That Exposes Everything

A $350 optic turned into an $18,000 problem. Not because the optic failed — because nobody cleaned the connector.

Rene Fichtmueller / 2026-04-05 / ~1 min read min read