How Linear Pluggable Optics (LPO) Are Reshaping 400G & 800G Data-Centre Networks in Europe

Modern data-centres and AI infrastructures are facing a twin challenge: exploding bandwidth demand and tightening power/thermal budgets. As cloud providers, HPC clusters and telcos ramp up 400G and 800G deployments, conventional optical transceivers are hitting efficiency, cost and latency limits.
That’s where Linear Pluggable Optics (LPO) come in — and they’re poised to become a mainstream choice for Europe’s next-gen fabric.

The technology shift: from DSP-centric to host-centric

Most high-speed optical modules today use a DSP (Digital Signal Processor) within the module to manage retiming, equalisation and FEC. While effective, the DSP architecture adds power consumption, latency, and cost.
LPO modules remove the internal DSP and shift key signal-processing tasks (equalisation, lensing, error-correction) to the host ASIC (switch or NIC). Instead of a full signal-processing stack inside the module, the module includes only high-linearity analog and optical components (such as TIAs, drivers, VCSELs) and relies on the host for digital processing.
This architecture offers three major advantages:

• Lower Power Consumption: Without the DSP, module power draw drops significantly (studies suggest up to ~50% lower).
• Reduced Latency: Fewer processing stages inside the module translate into shorter signal path delay.
• Simpler Thermal Design & Higher Density: Less heat means more compact optics, higher port density and improved rack-design flexibility.

Why LPO matters now — especially for Europe

Several market and technology trends make LPO especially relevant for European infrastructure:

• AI/ML & HPC growth: Clusters are increasingly intra-rack and inter-rack, where latency and power per link are critical.
• Data-centre energy constraints: European operators face higher energy/CO₂ costs and tighter sustainability targets. Lower power optics help reduce OPEX and cooling requirements.
• Supply-chain and regional compliance risks: European companies increasingly value “EU-tested”, “local support”, and supply-chain resilience over commodity optics. By offering EU-tested LPO modules, you address this demand.
• Bandwidth explosion + fabric densification: As networks go from 400G → 800G → beyond, the power/latency per link becomes a key metric. LPO offers an efficiency lever at scale.

Where LPO delivers best value (and where it doesn’t)

Ideal deployment scenarios for LPO:

• Leaf-spine fabrics inside data centres where links are predictable (intra-rack, rack-to-rack)
• AI/ML clusters where jitter/latency directly affect training time
• Edge data centres or telco sites with constrained power budgets
• Early deployments of 400G/800G where operators want to maximise performance per watt

Limitations / trade-offs:

• Because the host ASIC must support linear-drive signalling, not all platforms are compatible out-of-the-box. Proper qualification is essential.
• For longer or less controlled links (e.g., >500 m, unpredictable fibre conditions), DSP-based modules still have higher tolerance to impairments. As noted in the FLEXOPTIX article: “For longer or less predictable links … DSP-based optics remain the preferred option.”
• LPO ecosystem is still maturing — compatibility matrices, qualification reports, and host support are evolving.

Standards & ecosystem: how friction is being removed

Adoption of LPO is fuelled by industry standards that ensure interoperability and ecosystem maturity:

• LPO MSA (Multi-Source Agreement): Defines module architecture without a DSP, host-managed equalisation, and standardised monitoring functions.
• Optical Internetworking Forum (OIF) CEI-112G Linear PAM4 specification: Defines the high-speed electrical interface between host and module for 112 Gb/s per lane (enabling 400G/800G LPO).
• CMIS (Common Management Interface Specification) v4.x: Expands module management functions, enabling hosts to identify LPO modules, negotiate parameters, report power/temperature and support updates.

These standards mean that network designers can expect a plug-and-play path for LPO modules — provided the host platforms are qualified and certified.

Swedish Telecom Opto’s LPO Series: EU-tested, enterprise-ready

At Swedish Telecom Opto we are proud to launch our LPO Series, designed for European data-centres, telcos and hyperscale OEMs. Key features of our offering include:

• Four initial models covering 400G and 800G in QSFP112, OSFP800 and QSFP-DD form-factors.
• Full EU lab validation of power consumption, latency, signal integrity and thermal performance — enabling European operators to deploy with confidence.
• Fast European delivery, EU-invoicing and optional white-label branding to suit integrators and OEMs.
• Pre-qualification support for major switch/NIC vendors to ensure compatibility and reduce deployment risk.

Key specs of our initial models

What this means for you

• Lower OPEX: Lower power per port means fewer cooling and energy costs — particularly impactful at hyperscale or AI/ML scale.
• Lower latency: Improved synchronization and throughput for AI training and HPC workloads.
• Faster time-to-deploy in Europe: With EU-testing and local logistics you avoid long lead-times and customs delays.
• Better differentiation: For system integrators and OEMs — offer “EU-origin low-power 800G optics” as a service differentiator.

Next steps for data-centre and telco operators

1. Verify host platform support: Ensure your switch or NIC supports linear-drive signalling and LPO modules.
2. Request evaluation modules: We offer pilot units with full EU-lab performance results.
3. Plan deployment: Use our compatibility matrix and application notes to integrate with your leaf–spine fabric or AI cluster.
4. Measure impact: Track watts-per-Gb, latency improvement and cooling head-room before full roll-out.

The road ahead

The optics industry continues to evolve. Building on LPO, the next frontier includes Linear Receiver Optics (LRO) — combining analog receivers with smarter host-side processing — and Co-Packaged Optics (CPO), which integrate optics directly with switching ASICs.
By positioning now with LPO, European operators gain a key competitive advantage in power-efficient, high-speed connectivity.

Ready to explore our LPO Series?

Visit LPO Series or Request a Quote today and discover how you can upgrade your optical network for the demands of 400G/800G and beyond.

Josef Beach

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