Bharat Lanka Cable System: A regional link between India and Sri Lanka
The Bharat Lanka Cable System is a submarine telecommunications cable connecting India and Sri Lanka. Spanning approximately 325 kilometers, it links
Tuticorine in India with
Mt. Lavinia in Sri Lanka. Operated jointly by Bharat Sanchar Nigam Ltd. (BSNL) and Sri Lanka Telecom, the cable has been listed as in service since 2006, according to GeoCables records. Its primary purpose is to facilitate regional connectivity and support the growing demand for cross-border data exchange between the two countries.
What makes this cable particularly interesting is the scarcity of publicly disclosed technical details, such as its design capacity, number of fiber pairs, and supplier information. While its relatively short length suggests it is optimized for regional traffic, the lack of transparency leaves room for speculation about its technological specifications and performance.
Quick facts
| Cable name | Bharat Lanka Cable System |
| Length | 325 km |
| Ready for service | 2006 (GeoCables database value) |
| Owners | Bharat Sanchar Nigam Ltd. (BSNL), Sri Lanka Telecom |
| Status | In service |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Landing points | Mt. Lavinia (Sri Lanka); Tuticorine (India) |
| Other cables at Mt. Lavinia | Maldives Sri Lanka Cable (MSC) |
Route
The Bharat Lanka Cable System connects two landing points: Mt. Lavinia in Sri Lanka and Tuticorine in India. Mt. Lavinia is a coastal suburb of Colombo, the capital of Sri Lanka, while Tuticorine (also known as Thoothukudi) is a port city in the southern Indian state of Tamil Nadu. The cable traverses a relatively short distance across the Palk Strait, a narrow body of water separating the two countries. This geographic corridor is significant for regional connectivity, as it bridges the telecommunications infrastructure of South Asia.
Why it was built and what it carries
The cable was built to enhance connectivity between India and Sri Lanka, two neighboring countries with growing economic and digital ties. It supports voice, data, and internet traffic, serving as a critical link for businesses, government institutions, and consumers in both nations. The cable's regional scope suggests it is primarily used for intra-regional data exchange rather than global transit.
History: what can be established
GeoCables records indicate that the Bharat Lanka Cable System was ready for service in 2006. However, public sources do not provide corroborating evidence or alternative dates for its commissioning. This absence of detailed historical documentation limits the ability to cross-verify the timeline. The joint ownership by BSNL and Sri Lanka Telecom reflects a cooperative effort to strengthen bilateral telecommunications infrastructure.
Capacity and technology
The design capacity of the Bharat Lanka Cable System is not publicly disclosed, nor are details about its fiber pairs, supplier, or technology. Without operator documentation, it is impossible to state whether the cable has been upgraded since its initial deployment or what specific technologies it employs. As a relatively short regional cable, it is likely designed to handle moderate traffic volumes compared to larger intercontinental systems.
Latency: the physics
Theoretical one-way latency for light propagation over the 325 km wet segment is approximately 1.6 milliseconds, resulting in a round-trip time (RTT) floor of 3.2 milliseconds. However, real-world latency measurements are significantly higher due to additional factors such as land tails, terminal equipment, and routing. GeoCables live measurements show the following RTT values for internet traffic involving Tuticorine and Mt. Lavinia:
- Mt. Lavinia -> Tuticorine: min 34.2 ms, avg 49.3 ms
- Tuticorine -> Mt. Lavinia: min 16.8 ms, avg 32.5 ms
These figures reflect the full internet path rather than the cable alone, incorporating delays from terrestrial networks and intermediate nodes. The disparity between theoretical and observed latency underscores the complexity of end-to-end data transmission.
Redundancy: what happens if it breaks
In the event of a failure, redundancy for traffic routed through the Bharat Lanka Cable System would depend on alternative cables and terrestrial networks. At Mt. Lavinia, the Maldives Sri Lanka Cable (MSC) provides another submarine link, although it connects Sri Lanka to the Maldives rather than India. Terrestrial routes and satellite systems could also serve as backup, but they would likely introduce higher latency and reduced bandwidth compared to the submarine cable.
Repairing submarine cables typically involves deploying specialized cable ships equipped to locate, retrieve, and repair damaged sections. Given the relatively short length of the Bharat Lanka Cable System, repair operations would likely be faster and less complex than for longer intercontinental cables.
Bottom line
- The Bharat Lanka Cable System spans 325 km, connecting Tuticorine (India) and Mt. Lavinia (Sri Lanka).
- Owned by BSNL and Sri Lanka Telecom, it has been listed as in service since 2006.
- Design capacity, fiber pairs, supplier, and technology details are not publicly disclosed.
- Theoretical RTT over the wet segment is 3.2 ms, but real-world measurements show much higher latency due to additional network factors.
- Redundancy options include the Maldives Sri Lanka Cable (MSC) and terrestrial networks.