Insights

ACE Subsea Cable Upgraded Past 30 Tb/s on Existing Fiber

Published by TUOLAN TRADE on 2026-09-24 · Updated 2026-09-27

Submarine cable landing station interior with coherent optical transmission racks and a network engineer

INDUSTRY NEWS · FIBER OPTIC CABLES · SEPTEMBER 2026

The Africa–Europe (ACE) submarine cable consortium chose Ciena to upgrade one of its key routes — roughly 17,000 km across 18 landing stations — to more than 30 Tb/s using WaveLogic 6 Extreme, deployed onto the existing subsea line terminal equipment. No new cable is being laid. That is the part buyers should notice.

Submarine capacity announcements usually mean new fibre. This one does not. ACE is upgrading an in-service system by replacing the coherent engine: Ciena 6500 platforms driven by WaveLogic 6 Extreme (WL6e) are being deployed onto ACE’s existing submarine line terminal equipment, taking the route past 30 Tb/s while avoiding the traffic migration that a full terminal replacement would require. Ciena Services is handling deployment and ongoing maintenance, and the consortium is using Navigator for service visibility plus Liquid Spectrum’s Channel Margin Gauge to read wavelength signal-to-noise margin in real time.

ACE runs about 17,000 km across 18 landing stations, linking Western Europe, West Africa and South Africa. The consortium’s management committee frames the upgrade as a capacity path covering more than 500 million people.

Why an engine swap beats a new cable

The economics of submarine capacity have shifted. Laying new fibre costs capital, permits and years; upgrading the coherent engine on an existing wet plant costs a fraction of that and can be scheduled into normal maintenance windows. When a generation of coherent DSP delivers a large per-wavelength step — as WL6e does at 1.6T-class per-wavelength rates — the cheapest incremental capacity on a long-haul route is often optical, not physical.

For suppliers further up the chain, this changes the demand signal. A cable-layer order pulls fibre, repeaters and marine services. A coherent upgrade pulls line cards, coherent DSP, high-performance optical modules, amplifiers and testing — and it does so across the whole installed base rather than one new route.

What this means for cable and module sourcing

Watch the coherent module, not the fibre count. If upgrades dominate, the growth is in 400G/800G/1.6T coherent modules and their optical subassemblies rather than in additional fibre kilometres.
Channel margin becomes a purchasing metric. Margin-gauge tooling exists because operators buy capacity they can actually turn on. Suppliers who can present measured OSNR margin data win more easily than those quoting nominal reach.
Long-haul and subsea need different qualification evidence. A module qualified for a data-centre interconnect is not automatically qualified for a 17,000 km wet plant. Ask for the terminal-level test evidence, not just the module datasheet.
Deployment services are part of the product. ACE selected a vendor that also performs the installation and maintenance. When you quote into carrier programmes, state your field-support and spares position explicitly.

Optical Transceivers & Coherent Modules →

How to specify coherent optics for long-haul and subsea

Per-wavelength rate and baud. Fix the line rate and symbol rate first; everything else — FEC, DSP generation, module form factor — follows from those two numbers.
Reach class and margin. Specify the required OSNR margin at end of life, not nominal reach. Long-haul quotes without margin assumptions cannot be compared.
Form factor and power envelope. Coherent pluggables and chassis-based line cards have different thermal and density profiles. Decide which the terminal can actually accept.
Compensation and equalisation. Confirm CD/PMD compensation expectations and whether the DSP generation handles them internally.
Test and acceptance. Agree the terminal-level acceptance test — OSNR, pre-FEC BER, spectral shape — before shipment, not at landing.

Macro photograph of a coherent optical engine module showing connector array and DSP board — The coherent engine is where a subsea upgrade actually happens: DSP generation, modulator and optical front end determine the per-wavelength step.

Sourcing fibre optic cable and coherent modules from China?

TUOLAN TRADE helps overseas buyers match long-haul and subsea requirements to the right fibre cable construction and transceiver class, compare coherent module options on reach and margin, and coordinate sample testing, documentation and export handling. Send your specification to sales@tuolango.com.

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Sources and disclosure

Figures are compiled from public internet sources dated September 2026: Fibre Optics Online (c-fol.net) reporting, citing Ciena, that the Africa–Europe (ACE) submarine cable consortium selected Ciena to upgrade a key route of approximately 17,000 km with 18 landing stations using WaveLogic 6 Extreme on the Ciena 6500 platform, delivering more than 30 Tb/s, with Ciena Services performing deployment and maintenance. Quoted capacity, distance and station counts are the supplier’s and consortium’s own published figures and are not independently verified here. Editorial analysis and sourcing guidance in this article are our own assessment. TUOLAN TRADE is not affiliated with any company mentioned; company and product names belong to their respective owners.