Trans-Caspian Fiber Optic Cable Project: Connecting Kazakhstan and Azerbaijan
The Trans-Caspian Fiber Optic Cable Project is a submarine cable system linking
Aktau in Kazakhstan to
Sumgait in Azerbaijan across the Caspian Sea. Spanning 341 kilometers, it is designed to facilitate high-speed data transmission between Central Asia and the Caucasus region. The cable is owned jointly by Azertelecom and Kazakhtelecom, two prominent telecommunications operators in their respective countries.
While the cable is listed as "in service" in GeoCables records, its recorded ready-for-service (RFS) date is 2026. This raises questions about the timeline of its operational status, as industry sources have yet to confirm this date or provide alternative estimates. Additionally, key technical specifications such as design capacity, fiber pair count, supplier, and technology remain undisclosed, leaving room for speculation about its capabilities.
Quick facts
| System name | Trans-Caspian Fiber Optic Cable Project |
| Length | 341 km |
| Ready-for-service date | 2026 (GeoCables database) |
| Status | Listed as in service |
| Owners | Azertelecom, Kazakhtelecom |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Technology | Not disclosed |
| Landing points | Aktau (Kazakhstan), Sumgait (Azerbaijan) |
Route
The cable connects the port city of Aktau on Kazakhstan's eastern Caspian coast to Sumgait, a major industrial center near Baku in Azerbaijan. This corridor traverses the Caspian Sea, a region of growing geopolitical and economic significance. The route is strategically positioned to enhance connectivity between Central Asia and the Caucasus, potentially serving as a critical link in broader Eurasian telecommunications networks.
Why it was built and what it carries
The Trans-Caspian Fiber Optic Cable Project was likely conceived to address the increasing demand for reliable, high-speed data transmission between Kazakhstan and Azerbaijan. Both countries are investing heavily in digital infrastructure as part of their economic modernization strategies. The cable could also play a role in facilitating international transit traffic, linking Central Asia to Europe via Azerbaijan's connections to Georgia and Turkey.
Specific information about the types of data carried by the cable has not been disclosed, but it is reasonable to assume it supports internet traffic, private enterprise communications, and government data exchanges.
History: what can be established
GeoCables records indicate a ready-for-service date of 2026, but the cable is already listed as "in service." This discrepancy could stem from several factors, such as phased operational milestones, differing definitions of "in service," or delays in public documentation. Without operator confirmation, the exact timeline remains unclear.
Both Azertelecom and Kazakhtelecom are established players in regional telecommunications, and their involvement suggests the project aligns with their strategic goals of expanding connectivity and capacity.
Capacity and technology
Publicly available data does not disclose the design capacity, fiber pair count, supplier, or technology used in the Trans-Caspian Fiber Optic Cable Project. These omissions make it difficult to assess the cable's performance or compare it with other systems in the region. Such information is typically proprietary and may only be revealed in operator statements or technical reports.
Latency: the physics
Theoretical one-way light propagation over the 341 km cable is approximately 1.7 milliseconds, with a round-trip time (RTT) floor of 3.3 milliseconds. However, real-world latency is significantly higher due to factors such as land tails, terminal equipment, and routing.
GeoCables live measurements, which capture the full internet path rather than the cable alone, show much higher RTTs. For example:
- Aktau to Sumgait: minimum 131.5 ms, average 136.0 ms
- Sumgait to Aktau: minimum 133.4 ms, average 136.1 ms
- Tbilisi to Sumgait: minimum 97.5 ms, average 97.5 ms
- Sydney to Sumgait: minimum 306.8 ms, average 307.3 ms
These values reflect the combined impact of terrestrial links, network congestion, and routing inefficiencies.
Redundancy: what happens if it breaks
In the event of a cable failure, redundancy would depend on alternative routes in the region. While specific alternatives are not listed in the GeoCables database, Kazakhstan and Azerbaijan are connected to broader terrestrial networks that could reroute traffic. Repairing a submarine cable typically involves deploying specialized vessels to locate and fix the damaged segment, a process that can take weeks depending on weather and logistical challenges.
Bottom line
- The Trans-Caspian Fiber Optic Cable Project spans 341 km between Aktau and Sumgait.
- Owned by Azertelecom and Kazakhtelecom, it is listed as "in service" despite a recorded RFS date of 2026.
- Key technical specifications, including design capacity and fiber pairs, are not publicly disclosed.
- Theoretical latency is low, but real-world measurements show significantly higher RTTs.
- Redundancy would rely on terrestrial networks and repair logistics in case of failure.