South Atlantic Inter Link (SAIL): Connecting South America and Africa
The South Atlantic Inter Link (SAIL) is a submarine telecommunications cable system spanning approximately 5,800 kilometers, linking
Fortaleza, Brazil, with
Kribi, Cameroon. Owned jointly by Camtel and China Unicom, it is listed as in service and provides a direct fiber-optic connection between South America and Africa, a corridor that has gained importance in recent years for intercontinental data traffic.
While the cable's operational status and route are clear, several technical and historical details remain undisclosed in publicly available sources. These include its design capacity, fiber pair count, supplier, and specific technologies employed. Additionally, discrepancies in recorded ready-for-service dates between GeoCables and other industry sources, if any, could complicate historical analysis.
Quick facts
| Length | 5,800 km |
| Ready-for-service year | 2020 (GeoCables database; conflicts with other sources not surfaced) |
| Owners | Camtel, China Unicom |
| Status | In service |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Landing points | Fortaleza (Brazil), Kribi (Cameroon) |
Route
The SAIL cable connects Fortaleza in northeastern Brazil to Kribi on the coast of Cameroon. Fortaleza is a major hub for submarine cables, hosting connections to numerous systems, including AMX-1,
BRUSA,
EllaLink,
GlobeNet,
Monet,
Project Waterworth, SAm-1, SAC, and SACS. Kribi, while less prominent than Fortaleza, is also a key landing site with connections to
Ceiba-2 and the
Nigeria Cameroon Submarine Cable System (NCSCS). This route provides a direct transatlantic link between South America and Africa, bypassing traditional routes through Europe or North America.
Why it was built and what it carries
The SAIL cable was built to improve connectivity between South America and Africa, regions historically underserved by direct submarine cable links. By connecting Fortaleza and Kribi, the system facilitates faster and more reliable data transfer between the continents, supporting economic growth, digital innovation, and international collaboration. While specific data on its traffic or utilization is not publicly disclosed, the cable likely carries a mix of internet, enterprise, and wholesale traffic, serving as a critical infrastructure for its owners and their customers.
History: what can be established
GeoCables records the SAIL cable as ready for service in 2020. If other industry sources suggest a different year, this discrepancy could stem from variations in defining the "ready-for-service" milestone-whether it refers to physical completion, testing, or commercial activation. Without additional documentation, the 2020 date remains the most reliable reference.
Capacity and technology
Publicly available information does not disclose the cable's design capacity, fiber pair count, supplier, or specific technologies. These unknowns make it difficult to assess its comparative performance or scalability. Such details are typically proprietary and often revealed only in operator or supplier documentation.
Latency: the physics
The computed one-way light propagation latency for SAIL's 5,800 km wet segment is approximately 28.4 milliseconds, with a theoretical round-trip time (RTT) floor of 56.9 milliseconds. Real-world RTT measurements are higher due to additional delays from land tails, terminal equipment, and routing.
GeoCables live measurements, which capture the full internet path rather than the cable alone, show significant variability. For Fortaleza to Kribi, the average RTT is 116.1 milliseconds across 116 checks, while Kribi to Fortaleza averages 287.1 milliseconds over 42 checks. A minimum RTT of 0.6 milliseconds was recorded in one direction, but this value is below the physical floor and is clearly an artifact caused by rate-limited ICMP replies from intermediate routers. Such artifacts underscore the limitations of remote probes in accurately measuring cable performance.
Redundancy: what happens if it breaks
In the event of a failure, traffic on SAIL could be rerouted via other cables landing at Fortaleza and Kribi. Fortaleza's extensive connectivity offers multiple alternatives, including SACS, which also connects South America to Africa, albeit via Angola. Kribi's redundancy options include Ceiba-2 and NCSCS, though these systems primarily serve regional rather than intercontinental routes. Repairing a submarine cable typically involves specialized vessels and can take weeks, depending on the nature of the fault and the availability of resources.
Bottom line
- SAIL spans 5,800 km, connecting Fortaleza (Brazil) to Kribi (Cameroon).
- Owned by Camtel and China Unicom, it has been in service since 2020 (GeoCables record).
- Design capacity, fiber pair count, supplier, and technology details are not publicly disclosed.
- Computed RTT floor for the wet segment is 56.9 ms; live measurements show higher values due to end-to-end path factors.
- Redundancy is available via other cables at Fortaleza and Kribi, though repair logistics remain complex.