The sea2shore submarine cable is a relatively short fiber optic system spanning 32 kilometers between Crescent Beach and Narragansett, both located in the United States. Owned by National Grid, the cable has been listed as in service since 2016 according to GeoCables records. Its primary purpose appears to be connecting these two coastal points, likely for regional utility or telecommunications purposes rather than international data traffic.
What makes sea2shore notable is its short length and the lack of publicly disclosed technical details, including design capacity, fiber pair count, supplier, and technology specifics. This absence of information limits a deeper understanding of its operational role, but it underscores the cable's niche function within its localized corridor. Public measurements of internet latency to Narragansett reflect the broader network path rather than the cable itself, making direct performance analysis of sea2shore challenging.
Quick facts
| Cable name | sea2shore |
| Length | 32 km |
| Ready-for-service year | 2016 (GeoCables database; no conflicting sources surfaced) |
| Owners | National Grid |
| Status | In service |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Technology | Not disclosed |
| Landing points | Crescent Beach (United States); Narragansett (United States) |
| Computed latency (one-way) | ≈ 0.2 ms |
| Computed latency (RTT floor) | ≈ 0.3 ms |
Route
The sea2shore cable connects Crescent Beach and Narragansett, two locations along the eastern coastline of the United States. Crescent Beach is situated on Block Island, Rhode Island, while Narragansett lies on the mainland, also in Rhode Island. The 32-kilometer route spans a relatively shallow and localized marine environment, likely avoiding deep-sea engineering challenges typical of transoceanic cables. This region is well-known for its coastal activities and utility infrastructure, which may provide context for the cable's purpose.
Why it was built and what it carries
While public documentation does not explicitly state the cable's function, its ownership by National Grid suggests it may serve utility-related purposes, such as supporting energy infrastructure or providing telecommunications services to Block Island. Submarine cables in such short corridors are often built to enhance connectivity for remote or semi-isolated areas, ensuring reliable communication and data transfer between the mainland and nearby islands.
History: what can be established
GeoCables records indicate that sea2shore became ready for service in 2016. No conflicting dates have surfaced in industry sources, which suggests this timeline is accurate. However, the absence of detailed public documentation limits further historical analysis, such as the cable's construction timeline, initial capacity planning, or any upgrades since its deployment.
Capacity and technology
The design capacity of sea2shore is not publicly disclosed, nor are details about its fiber pair count, supplier, or specific technology. Without operator documentation, attributing these parameters would be speculative. Given its short length and localized role, it is plausible that the cable employs relatively standard submarine fiber optic technology, but this cannot be confirmed.
Latency: the physics
The computed theoretical latency for sea2shore is approximately 0.2 milliseconds one-way and 0.3 milliseconds round-trip over the wet segment. This calculation assumes light propagation speeds of 200,000 to 204,000 kilometers per second in fiber. Real-world latency would be higher due to factors such as land-based network tails, terminal equipment delays, and routing overhead.
Live latency measurements to Narragansett from various global locations range widely, reflecting the broader internet path rather than the cable itself. For example:
- Saint Petersburg -> Narragansett: 108.1 ms
- Minsk -> Narragansett: 157.6 ms
- Kyiv -> Narragansett: 100.9 ms
- Moscow -> Narragansett: 116.4 ms
- Singapore -> Narragansett: 1.0 ms
- Sydney -> Narragansett: 218.1 ms
These figures include terrestrial and other submarine segments, making them unsuitable for isolating sea2shore's performance.
Redundancy: what happens if it breaks
Given its short length and localized role, sea2shore likely serves a specific niche that may not have direct redundancy. If the cable were to fail, alternative connectivity for Block Island might rely on existing terrestrial or wireless systems, but this is speculative without operator documentation. Repair logistics for such a short cable would typically involve rapid deployment of specialized vessels and equipment, as is standard practice in the submarine cable industry.
Bottom line
- sea2shore is a 32-kilometer submarine cable connecting Crescent Beach and Narragansett in Rhode Island, United States.
- Owned by National Grid, it has been in service since 2016 according to GeoCables records.
- Publicly available data does not disclose its design capacity, fiber pairs, supplier, or technology specifics.
- Theoretical latency over the wet segment is approximately 0.3 milliseconds round-trip, with real-world values being higher due to additional network factors.
- Its localized role suggests utility or regional telecommunications purposes, but specifics are not documented.