OFC 2026 – Scaling Up Optical Network Density

At OFC 2026, analyst Jimmy Yu frames optical networking’s next step as scaling density, citing new 100 Gbps to 1.6 Tbps pluggable optics, full-spectrum transponders, and multi-rail inline amplification approaches aimed at higher port and amplifier packing per unit volume.

ZR and ZR+ pluggable optics moving toward more DSP suppliers

Yu says 100 Gbps ZR/ZR+ QSFP28 pluggables have shipped for revenue since 4Q 2023, with shipments ramping, and notes the DSP sourcing changed at OFC. He writes that “two additional suppliers—Cisco Acacia and Arycs Technologies—announced plans to begin shipping their 100 Gbps ZR/ZR+ pluggable with in-house DSPs in mid-2026,” making three DSP suppliers.

Yu also ties the market setup to Dell’Oro Group forecasts, stating that “we forecast that 100 Gbps ZR/ZR+ optical pluggable modules will grow steadily for many years to come.”

800 Gbps ramp and announced timing for 1.6 Tbps pluggables

Yu reports that Cisco Acacia announced it had ramped 800 Gbps ZR/ZR+ DSP production, shipping “25,000 DSPs to date,” and contrasts that figure with industry cumulative shipments for 400 Gbps pluggables. He gives the industry cumulative total as “closer to 1.7 million” and adds that “Cisco Acacia has stated they shipped 750 thousand 400 Gbps DSPs to date.”

For 1.6 Tbps ZR/ZR+ pluggables in OSFP form factor with DSPs based on a 2 nm foundry process, Yu lists 1Finity, Ciena, Marvell, and Nokia and describes an expected General Availability (GA) “before the end of 2027,” with “samples as early as 4Q 2026.” He adds that “1Finity will use a 3rd party DSP,” and that Cisco Acacia “did not make any announcements about 1.6 Tbps optics at OFC,” with a belief that it would wait until ECOC.

Nokia outlines a pipeline spanning multiple coherent DSPs and module formats

Yu says Nokia presented its new optical pipeline at an analyst event, and he summarizes the scope as four planned coherent DSPs, plus multiple optics and system modules. He quotes Nokia’s framing as an “anywhere, anyplace, and anybody” strategy and attributes his interpretation to the event.

Yu says Nokia plans “Four new coherent DSPs (Huron, Superior, Ontario, and Pacific),” describing that “three of the four are being developed simultaneously, using the same 2 nm base structure and logic.” He assigns use cases including “3.2 Tbps coherent-lite for campus,” “1.6 Tbps ZR/ZR+ pluggable for metro and Data Center Interconnect (DCI),” and “2.4 Tbps high-performance for long-haul and subsea,” while also describing a double-sided pluggable transponder and a “multi-rail in-line amplifier (ILA)” with “the highest-density configuration” at “160 rails per rack,” with sampling “mid-2026.”

Ciena keeps more coherent DSP details internal while describing system-level products

Yu reports that Ciena announced multiple products under development while “kept much of the coherent DSP activity under wraps.” He lists an “6 Tbps ZR/ZR+ OSFP pluggable module for IPoDWDM,” a “2 Tbps coherent-lite plug for campus,” and “Reinforcement Learning Security (RLS) Hyper-rail, which is a multi-rail ILA,” with plans for “300 mm and 600 mm versions” and a “5 Resource Unit (RU) size.”

Yu also describes Ciena’s plans for a full-spectrum transponder that “outputs all the wavelengths through a single fiber connector” and states that “Early work on xPO modules was shown.” He adds that xPO’s liquid cooling helps allow a tighter configuration, according to his interpretation.

Multi-rail amplification and volumetric density as a network efficiency metric

Yu argues that as optical transponder technology approaches Shannon’s limit, spectral-efficiency gains do not increase fiber capacity, and he states that “each fiber pair requires an ILA every 80 km.” He also provides a scenario for GPU-to-GPU data center connectivity needing “20 Pbps of capacity” translating into “390 fiber pairs” for “800 ZR+ optics at each end,” and says this would require “three racks of multi-rail ILAs … at each site” if a rack supports “128 rails.”

He says four companies announced multi-rail products at OFC—Coherent Corp., Ciena, Cisco, and Nokia—and that “Molex, Ribbon, and Smartoptics” plan to look into developing a multi-rail system. He estimates that “commercial shipments of multi-rail products could begin in 2027.”

Density as the next dimension for system design

Yu frames a shift away from scaling by wavelength speeds and usable spectrum, describing density as “the next dimension,” with more transponders and ILAs packed into a cubic meter of space. He links multiple product themes—“1.6 Tbps ZR/ZR+ optics,” “xPO form factor pluggable module,” “Full Spectrum Transponder,” and “Multi-rail ILA”—to a projected “around 4 times” density increase when combined.

Yu concludes that optical transport system efficiency should be measured by “volumetric density (Gbps-per-cubic meter) rather than spectral efficiency (Gbps-per-hertz).”

This Analyst Signals brief reflects a neutral, fact-based summary of the original research note.