T3

T3 is a 3,200-kilometre submarine cable connecting Mauritius to South Africa, jointly owned by Mauritius Telecom and Liquid Intelligent Technologies. It went into service in 2023 and is one of the newer cables in the Indian Ocean, built specifically to break Mauritius out of its historic dependence on older, congested cables for international connectivity. For a small island nation with a population of 1.3 million and a growing financial-services economy, T3 matters disproportionately: it is the cable that lets Mauritian data reach South African peering without detouring through Europe.

Two owners, two landings, one clear purpose

T3 is a two-party cable, which makes it unusually simple for a modern submarine system. Mauritius Telecom is the island nation's state-controlled incumbent telecommunications operator; Liquid Intelligent Technologies is a pan-African data-centre and fibre-network operator, headquartered in Mauritius but with operations across more than 20 African countries. The partnership mirrors the structure of Tannat (Google + Antel Uruguay) but in an African context: one party brings local landing rights and national-market knowledge, the other brings capital and regional interconnection reach.

The purpose of T3 is to reduce Mauritius's dependence on older Indian Ocean cables. Before 2023, Mauritius connected to the global internet primarily through the SAFE cable (2002, nearly at end-of-life) and LION/LION2 (2010/2012), which route through Réunion and Madagascar respectively. These cables are decades old, increasingly unable to carry modern traffic levels, and route through cable landings that Mauritian carriers do not own. T3, by contrast, lands at Baie Jacotet on Mauritius's south coast at a station built specifically for this cable, with Liquid-operated backhaul inland. From Mauritius's perspective, T3 was long overdue and strategically essential.

Our measurements

We monitor T3 between Amanzimtoti (South Africa) and Baie Jacotet (Mauritius) — the cable's full east-west traversal of 3,200 kilometres. Over 30 days we have 63 clean samples across both directions:

The Amanzimtoti → Baie Jacotet direction delivers a 48.8-ms minimum with a 63.6-ms average — stable, consistent latency reflecting the cable's 3,200-km length plus the normal overhead of repeaters and terrestrial tails. The physics floor for this path is 31.3 ms, so the observed minimum is about 55% above the floor, which is on the higher side for a well-engineered cable but not unusual for a cable with only four fibre pairs and simpler branching architecture.

The Baie Jacotet → Amanzimtoti direction is where T3's story becomes interesting. A 181.9-ms minimum — nearly four times the outbound minimum — indicates that return traffic from Mauritius is not using T3 itself, but rather an older path back through Europe. The 133-ms asymmetry gap is consistent with a Mauritius → Marseille → South Africa routing, which is approximately 18,000 additional kilometres of fibre compared with the direct T3 path. Mauritius-originated outbound traffic, in other words, is still predominantly routing through European peering relationships, even though a direct South African path exists.

Why the asymmetry persists

This is the same pattern we see on other new African cables like NCSCS: when a cable is new and locally owned, it becomes the default for inbound traffic because the destination's routing preferences naturally favour using the cable that ends at its landing station. But outbound traffic, especially from a small island, is governed by upstream transit contracts with European Tier-1 carriers that were negotiated years before T3 existed. These contracts include committed volumes and route preferences that take years to unwind.

Mauritius Telecom and Liquid could in principle reconfigure Mauritius's outbound routing to prefer T3, but doing so requires renegotiating upstream contracts, retraining network operations staff, and accepting whatever commercial terms the South African carriers offer on the other end. Incremental renegotiation over the next several years will gradually shift the asymmetry — but it will not happen in a single re-cabling event. What we are observing is the interim: the physical cable is live and carrying traffic, but the commercial conventions surrounding it still treat Europe as the default egress.

T3 and Liquid's African strategy

T3 is one piece of Liquid Intelligent Technologies' broader Indian Ocean and African strategy. Liquid operates data centres across Africa, owns terrestrial fibre backbone through Southern, East, and Central Africa, and is a partner on the 2Africa cable as one of its landing operators. T3 gives Liquid Indian Ocean presence without having to partner with one of the continent-circling mega-cables. For a company that sells capacity and data-centre services to African enterprises, owning the short-haul cable between Mauritius and South Africa means better economics for Mauritian customers and a direct path to South African peering for its cross-regional services.

The Amanzimtoti landing is notable. Amanzimtoti is a coastal town in KwaZulu-Natal, roughly 25 kilometres south of Durban. It is not the traditional African cable landing point — most East African cables land at Mtunzini (Richards Bay area) or Melkbosstrand (Cape Town). Amanzimtoti is a deliberate choice: it is Liquid's own landing station, not a cable-hotel owned by a competitor, and it connects directly to Liquid-operated terrestrial fibre into Durban and the South African backbone. This vertical integration — owning the cable, the landing, and the downstream fibre — is what allows T3 to compete economically with older consortium cables.

What T3 changes for Mauritius

For Mauritius, T3 is the infrastructure that makes the country's financial-services industry credible as a regional data hub. Before 2023, the latency from Mauritius to Johannesburg was higher and less predictable than it is today, because traffic detoured through Europe and back. Now, at least for inbound services, Mauritian data centres can offer South African customers a clean 48 ms round-trip. That is competitive with intra-South Africa latencies and changes what sort of services can be economically hosted in Mauritius.

Whether Mauritius realises the economic opportunity that T3 creates will depend less on the cable and more on the broader financial-services and regulatory environment. But the physical infrastructure is now in place, and our measurements show it is operational exactly as designed — at least in one direction.

Try it yourself

Live latency data on the T3 cable page. For regional context see 2Africa (the pan-African cable that also lands in the region) and SAFE (Mauritius's older Indian Ocean cable, now near end-of-life). Our measurements refresh every two hours.