Sorsogon-Samar Submarine Fiber Optical Interconnection Project (SSSFOIP)

Sorsogon-Samar Submarine Fiber Optical Interconnection Project (SSSFOIP): Connecting Luzon and Samar

The Sorsogon-Samar Submarine Fiber Optical Interconnection Project (SSSFOIP) is a submarine cable linking Allen in Northern Samar to Santa Magdalena in Sorsogon, Luzon, Philippines. Spanning 21 kilometers, this cable is owned by the National Grid Corporation of the Philippines and was recorded as ready for service in 2019 according to GeoCables data. Its primary role is to enhance connectivity between Luzon and Samar, two major islands in the Philippines. What makes this cable particularly interesting is the limited public disclosure about its technical specifications, such as design capacity, fiber pair count, supplier, and technology. This lack of transparency contrasts with other submarine cables in the region, which often have more detailed documentation. Additionally, latency measurements from remote probes show significant real-world delays, highlighting the complexity of end-to-end internet routing beyond the cable itself.

Quick facts

Length	21 km
Ready for Service (RFS)	2019 (GeoCables database)
Owner	National Grid Corporation of the Philippines
Status	In service
Design Capacity	Not disclosed
Fiber Pairs	Not disclosed
Supplier	Not disclosed
Technology	Not disclosed
Landing Points	Allen (Philippines); Santa Magdalena (Philippines)
Other cables at Allen	Submarine Cable in the Philippines (SCiP)

Show Sorsogon-Samar Submarine Fiber Optical Interconnection Project (SSSFOIP) on the interactive cable map

Route

The SSSFOIP connects Allen, a municipality in Northern Samar, to Santa Magdalena, a coastal town in Sorsogon province on Luzon island. This short 21-kilometer route crosses the San Bernardino Strait, a narrow body of water separating Luzon from Samar. The corridor is strategically important for linking the two islands, which are part of the Philippines' eastern maritime region. Allen serves as a landing site for other submarine cables, such as the Submarine Cable in the Philippines (SCiP), indicating its role as a regional connectivity hub. Santa Magdalena, while less prominent, is a logical landing point due to its proximity to Allen across the strait.

Why it was built and what it carries

The SSSFOIP was built to improve telecommunications infrastructure between Luzon and Samar, facilitating faster and more reliable data transmission across the San Bernardino Strait. As part of the Philippines' broader efforts to enhance connectivity, this cable supports local and regional internet traffic, as well as critical communications for businesses and government operations. While specific details about its capacity and technology are not publicly available, its ownership by the National Grid Corporation of the Philippines suggests it may also play a role in supporting grid-related communications infrastructure.

History: what can be established

GeoCables data records the SSSFOIP as ready for service in 2019. No conflicting dates have been identified in publicly available industry sources, so this year is accepted as the most reliable reference for its operational start. The cable's construction aligns with the Philippines' ongoing efforts to expand and modernize its telecommunications network, particularly in underserved regions. However, the absence of detailed public documentation about its development and deployment limits further historical analysis.

Capacity and technology

Publicly available data does not disclose the SSSFOIP's design capacity, fiber pair count, supplier, or specific technology. Without operator documentation, attributing these parameters would be speculative. It is therefore unclear how this cable compares technologically to others in the region, such as the Submarine Cable in the Philippines (SCiP), which also lands at Allen.

Latency: the physics

Theoretical calculations suggest that light propagation over the 21-kilometer wet segment of the SSSFOIP would result in a one-way latency floor of approximately 0.1 milliseconds, with a round-trip time (RTT) floor of 0.2 milliseconds. However, real-world latency measurements are significantly higher due to factors such as land tails, terminal equipment, and routing. Remote probes measuring the full internet path to Allen indicate the following latencies:

• Singapore -> Allen: minimum 36.9 ms, average 37.0 ms
• Almaty -> Allen: minimum 241.7 ms, average 241.8 ms
• Sao Paulo -> Allen: minimum 381.3 ms, average 498.0 ms

These values reflect the combined impact of the cable, terrestrial infrastructure, and global routing inefficiencies, rather than the cable's isolated performance.

Redundancy: what happens if it breaks

In the event of a failure, redundancy for the SSSFOIP may be partially supported by the Submarine Cable in the Philippines (SCiP), which also lands at Allen. However, the extent to which SCiP or other regional cables could absorb traffic is not documented. Standard industry practices for submarine cable repair include deploying specialized cable-laying vessels to locate and fix faults, which can be time-consuming depending on weather conditions and the nature of the damage.

Bottom line

• The SSSFOIP spans 21 kilometers, connecting Allen (Samar) to Santa Magdalena (Luzon).
• It was recorded as ready for service in 2019, with no conflicting dates identified.
• Owned by the National Grid Corporation of the Philippines, its technical specifications remain undisclosed.
• Theoretical latency over the wet segment is extremely low, but real-world measurements show much higher values due to routing and equipment factors.
• Redundancy may be partially supported by SCiP, but specifics are unclear.