A consortium of global and African telecommunications partners announced the 2Africa subsea cable project with a design capacity of up to 180 terabits per second on key segments, a figure that places a single modern cable squarely in the “hundreds of terabits” range. The system relies on a fiber technology called SDM1, which doubles the number of fiber pairs available inside one cable from the eight pairs common in older designs to 16. That technical leap carries direct consequences for how quickly operators can scale internet capacity across Africa and beyond without laying additional cable on the ocean floor.
How 16 fiber pairs change the economics of undersea bandwidth
Older subsea cables typically carried eight fiber pairs. Each pair functions as an independent data highway, and operators activate pairs incrementally as traffic demand grows. When all eight pairs are lit, the only way to add capacity is to build and install an entirely new cable, a process that takes years and costs hundreds of millions of dollars. The 2Africa project, backed by partners including Facebook (now Meta), Vodafone, Orange, and Telecom Egypt, uses SDM1 technology enabling up to 16 fiber pairs inside a single cable. That means operators can activate additional pairs one at a time as demand rises, without dispatching cable ships or negotiating new seabed permits.
The practical result is that a cable built with 16 fiber pairs offers twice the runway for incremental growth compared with an eight-pair system. Operators can respond to surging traffic by lighting a new pair in weeks rather than waiting years for a new marine installation. This dynamic supports the hypothesis that 16-pair cables will reach commercial traffic levels faster than their eight-pair predecessors, because each activation step requires only shore-side equipment upgrades instead of ocean-floor construction. The extra fiber pairs function as built-in insurance against demand spikes driven by mobile data, cloud computing, and streaming video across fast-growing markets.
From a financial perspective, the extended growth path changes how investors and carriers think about risk. A traditional eight-pair system forces a binary choice: either live with congestion as demand outstrips lit capacity, or commit early to a new cable. A 16-pair design lets operators defer that cliff. They can purchase and light capacity in smaller increments over a longer period, aligning capital spending more closely with revenue. That flexibility is particularly important in emerging markets, where traffic forecasts are uncertain and currency volatility can complicate long-term infrastructure bets.
2Africa’s 180 Tbps design target and what it rests on
The consortium’s announcement states that 2Africa has a design capacity of up to 180 Tbps on key parts of the system. That number represents the theoretical maximum when all 16 fiber pairs are fully activated and equipped with the latest optical transmission gear. At 180 Tbps, a single cable could carry the equivalent of millions of simultaneous high-definition video streams or handle the combined internet traffic of entire nations.
The 180 Tbps figure is a design ceiling, not a day-one operating rate. Subsea cable operators rarely light every fiber pair at launch. Instead, they activate capacity in stages, matching investment to actual customer demand. The gap between design capacity and real-world throughput is significant, and no independent technical audit of achieved throughput has been published as of the consortium’s announcement. The distinction matters for anyone evaluating whether “hundreds of terabits” describes current performance or future potential. Based on the consortium’s own disclosures, it describes the engineered upper limit of the system.
SDM1, the technology behind 2Africa, stands for Space Division Multiplexing. By packing more fiber pairs into the same cable diameter that previously held eight, SDM1 reduces the cost per bit of capacity. Each fiber pair can carry multiple wavelengths of light, and each wavelength can be modulated at high data rates. Stacking 16 pairs together multiplies total throughput without proportionally increasing the cable’s physical size or the complexity of its ocean-floor repeaters. The result is a single cable that rivals the combined capacity of several older systems.
This architecture also has implications for future upgrades. Optical transmission equipment improves over time, allowing more bits to be pushed over the same glass. Because the fibers are already in place, operators can raise total capacity by upgrading terminal equipment onshore rather than disturbing the seabed. In practice, that means the 180 Tbps design target could be approached in stages through successive generations of optics, stretching the useful life of the cable and spreading its capital cost over many years of service.
Gaps in the record: utilization, access, and real traffic
Several questions remain open. First, no official operator statement has disclosed how many of 2Africa’s 16 fiber pairs have been activated or what fraction of the 180 Tbps ceiling is carrying live traffic. Without those numbers, it is difficult to assess whether the system is already delivering hundreds of terabits per second or still ramping up. Early in a cable’s life, it is common for only a subset of pairs to be lit, leaving substantial headroom for growth.
Second, the consortium’s public materials do not detail landing-point ownership structures or access pricing in the African countries where the cable comes ashore. Landing stations are the physical gateways between undersea cables and national networks. Who owns them and at what price local internet providers can connect determines whether the cable’s capacity actually translates into cheaper, faster internet for end users. A cable with 180 Tbps of design capacity does little for consumers if access fees at the landing station remain high or if a small number of operators control the on-ramp.
Third, the 2Africa announcement was made by consortium partners with a direct commercial interest in promoting the project’s scale. Independent verification of throughput performance, once the system reaches full operation, would strengthen the technical claims. Until such data appears, the 180 Tbps figure should be understood as a manufacturer-grade specification rather than a field-tested measurement. Industry observers will be watching for neutral performance reports and for regulatory filings that might disclose more detail about the system’s actual usage.
For businesses and governments planning digital infrastructure investments in Africa and the Middle East, the next development to watch is whether operators publish utilization data as fiber pairs are activated. That information will reveal how quickly the 16-pair architecture converts theoretical capacity into live traffic and whether demand growth is tracking the optimistic forecasts used to justify the build. Transparent reporting would also help policymakers decide where to focus complementary investments, such as terrestrial fiber backbones and data centers that can take advantage of new international bandwidth.
At the same time, national regulators and competition authorities will face decisions about how to govern access to landing stations. Rules that encourage open, non-discriminatory interconnection can spread the benefits of 2Africa’s capacity across a wider range of internet service providers, potentially lowering retail prices and improving service quality. By contrast, permissive regimes that allow exclusive control of landing facilities risk entrenching incumbents and limiting the impact of the new cable on market dynamics.
Ultimately, the 2Africa project illustrates both the promise and the limits of headline capacity figures. Engineering advances like SDM1 and 16 fiber pairs make it technically feasible for a single cable to reach 180 Tbps, placing Africa’s coastal infrastructure on par with the most advanced routes in the world. Yet the lived experience of users will depend on how quickly operators light those fibers, how competitively they price access at landing points, and how effectively countries build out their domestic networks. Until more detailed utilization and pricing data becomes public, 2Africa should be viewed as a powerful platform whose real impact will unfold over the coming years rather than as a fully realized “hundreds of terabits” pipeline on day one.
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*This article was researched with the help of AI, with human editors creating the final content.
