Columbus-II b: A Legacy Submarine Cable
The Columbus-II b submarine cable is a telecommunications system connecting
Magen’s Bay in the United States Virgin Islands to
West Palm Beach, Florida, USA. With a length of 2068 kilometers, it is owned by AT&T and Setar and has been listed as in service since its recorded ready-for-service (RFS) year of 1994. However, details about its design capacity, fiber pairs, supplier, and technology have not been disclosed in public sources, leaving certain aspects of its technical profile unknown.
This cable is part of the Columbus-II system, a broader network that historically linked multiple locations across the Atlantic and the Caribbean. Columbus-II b serves as a regional segment, and its continued operation highlights the enduring relevance of older submarine cables in the global telecommunications landscape. Despite its age, it remains an active link in the region, contributing to connectivity between the Caribbean and mainland United States.
Quick facts
| Cable name | Columbus-II b |
| Length | 2068 km |
| Ready-for-service year | 1994 (GeoCables database value; no conflicting industry sources surfaced) |
| Owners | AT&T, Setar |
| Status | In service |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Technology | Not disclosed |
Route
The Columbus-II b cable connects two landing points: Magen’s Bay in the United States Virgin Islands and West Palm Beach in Florida, USA. Magen’s Bay is a notable landing site, hosting other submarine cables such as
Americas-I North and
Taino-Carib, which contribute to the region's connectivity. The corridor spans the Caribbean Sea, providing a direct link between the U.S. mainland and the Virgin Islands.
Why it was built and what it carries
The Columbus-II b cable was built as part of the Columbus-II system to enhance telecommunications infrastructure in the Caribbean and support growing demand for international connectivity. It provides a critical link between the Virgin Islands and the mainland United States, facilitating voice, data, and internet traffic. While specific data on its current usage and traffic volumes are not publicly available, its continued operation suggests it plays a role in regional telecommunications, either as a primary route or as redundancy for other systems.
History: what can be established
The GeoCables database records Columbus-II b as having entered service in 1994. No conflicting dates have surfaced in industry sources, so this year is taken as the most reliable. The cable was developed during a period of significant expansion in submarine telecommunications, as operators worked to meet increasing demand for international connectivity in the Americas and the Caribbean. Ownership by AT&T and Setar reflects collaboration between U.S. and Caribbean entities, a common practice in regional cable systems.
Capacity and technology
Publicly available data does not disclose the design capacity, fiber pair count, supplier, or specific technology used in Columbus-II b. Without operator documentation, these details cannot be reliably stated. Given its 1994 RFS year, it is likely based on older optical fiber technology, but attributing specific specifications would be speculative. Modern upgrades, if any, have not been documented in public sources.
Latency: the physics
The computed one-way light propagation latency for Columbus-II b over its 2068 km length is approximately 10.1 milliseconds, with a theoretical round-trip time (RTT) floor of 20.3 milliseconds for the wet segment. Real-world latency measurements would be higher due to factors such as land tails, terminal equipment, and routing. No live measurements for this cable are currently available, so its actual performance cannot be assessed beyond theoretical calculations.
Redundancy: what happens if it breaks
If Columbus-II b were to experience a fault, redundancy in the corridor is provided by other cables landing at Magen’s Bay, such as Americas-I North and Taino-Carib. These systems could potentially reroute traffic, mitigating the impact of an outage. Repair logistics for submarine cables typically involve deploying specialized cable ships to locate and fix the fault, a process that can take days to weeks depending on the nature and location of the damage.
Bottom line
- Columbus-II b connects Magen’s Bay, U.S. Virgin Islands, to West Palm Beach, Florida, USA.
- It spans 2068 km and has been listed as in service since 1994.
- Owned by AT&T and Setar, it is part of the larger Columbus-II system.
- Details on capacity, fiber pairs, supplier, and technology are not publicly disclosed.
- Computed latency floor is approximately 20.3 ms RTT, but real-world performance is higher.
- Redundancy is supported by other cables at Magen’s Bay, such as Americas-I North and Taino-Carib.