OFC 2026 – Amphenol: Dense Interconnect and Liquid Cooling — How the XPO Module Signals a Shift in AI Data Center Connectivity
At OFC 2026, the surge in AI compute demand has pushed traditional data center architecture to a tipping point. Amphenol made clear that as a single rack becomes the basic unit of compute, interconnect is no longer just about moving data — it is a combined test of space utilization, power management and thermal engineering. The talk focused on how innovative form factors such as XPO (Extra Dense Pluggable Optics) and built-in liquid cooling can carve out a pragmatic, highly scalable evolution path for AI data centers between the limits of copper and Co-Packaged Optics (CPO).
Core Technology: From the Limits of Copper to the Birth of XPO
1. Copper's "Physical Boundary" and Packaging Challenges
Although the industry predicts the end of copper every generation, Amphenol has successfully pushed 224 Gbps signals to the front panel by connecting TwinX cables right next to the chip (near-chip interface). Moving to the next generation, however, runs into two bottlenecks:
Breaking out of the BGA package: bandwidth loss when routing signals out of the ASIC package.
Pluggable I/O performance: at 224G and higher data rates, the electrical integrity of mechanical connectors faces major challenges.
2. The XPO Module: A Revolution in Density and Thermal Management
To address uncertainty around CPO's supply chain and serviceability, Amphenol introduced the XPO (Extra Dense Pluggable Optics) module, regarded as the highest-density pluggable optics solution in the industry today:
Ultra-high density: a single XPO module does the work of 8 OSFP modules. A 1U space can hold 16 XPO ports, delivering bandwidth density equal to a CPO switch. By comparison, a conventional OSFP design needs 4U of rack space to reach the same bandwidth.
Native liquid cooling: XPO completely drops traditional air-cooled heat sinks. Liquid inlet and outlet lines are integrated inside the module, directly solving the heat-removal problem of packing 8 OSFP modules' worth of function into a tiny space.
Low-power LPO path: the LPO (Linear Pluggable Optics) version developed for XPO targets power below 90W, which is critical for low-latency, energy-efficient AI interconnect.
3. Next-Gen Bandwidth Target: 130 GHz and the Modulation Debate
For future 400G-per-lane (448 Gbps) needs, Amphenol noted that test and validation bandwidth must reach 130 GHz. The key divide today is the choice of modulation:
PAM4 vs. PAM6/PAM8: staying with PAM4 requires the electrical interface to keep insertion loss low out to 115–120 GHz; moving to more complex modulation (such as PAM6) lowers the physical bandwidth requirement but has a major impact on ecosystem compatibility.
Supply Chain and Market Impact
Amphenol's strategy shows hardware vendors trying to strike a balance between "the convenience of pluggable modules" and "the high performance of CPO."
Supply chain stability: by driving the XPO MSA (Multi-Source Agreement), Amphenol aims to maintain a diverse supplier ecosystem and avoid the vertical-integration constraints and serviceability problems common in CPO solutions.
Spread of liquid cooling infrastructure: XPO modules mandate liquid cooling support, which will accelerate the shift of data center capex (CAPEX) from air-cooled to liquid-cooled architectures — a major market opportunity for industrial connector and thermal module makers.
Cross-domain applications: beyond Ethernet, Amphenol and Microchip demonstrated PCIe Gen 6 Over Optics. This shows optical technology reaching into the sideband and management planes at the heart of compute, further blurring the line between networking and computing.
Simple Tech Trend's View
Amphenol's XPO solution at OFC 2026 effectively buys pluggable modules at least 2–3 more years of "lifespan dividend."
Density is no longer CPO's exclusive domain: with 1 XPO = 8 OSFP, pluggables can now match CPO on faceplate density. This will make hyperscalers more cautious when evaluating a move to CPO, since existing service workflows and modularity advantages are preserved.
Liquid cooling is now mandatory: XPO marks a new era for optical modules — "no liquid cooling, no bandwidth." Over the next 12–24 months, how well liquid-cooling quick disconnects integrate with modules in the data center will become a core measure of hardware competitiveness.
The critical 400G window: by end-2026, the industry will reach an initial consensus on electrical modulation (PAM4/6/8). We expect LPO and half-retimed (LRO/RTLR) solutions to play a key role in XPO architectures to ease DSP-driven power pressure.
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