Meltingpot Indianoceanic Submarine System (METISS)

METISS: A Regional Submarine Cable Transforming Connectivity for Indian Ocean Islands

Meltingpot Indianoceanic Submarine System, or METISS, is a submarine fiber-optic system approximately 3,200 km in length, connecting Mauritius, Réunion, and Madagascar to the eastern coast of South Africa. Unlike intercontinental backbones that transit through the Indian Ocean, METISS was specifically designed as regional infrastructure: the islands gained their own direct route to South African communication hubs, data centers, and international operators.

The system's name stands for MEltingpoT Indianoceanic Submarine System. It reflects the idea of a joint project for the countries and territories of the southwestern Indian Ocean. METISS connects four points: Baie du Tombeau in Mauritius, Le Port in Réunion, Fort Dauphin in Madagascar, and the Umbogintwini/Amanzimtoti area south of Durban in South Africa.

Key Facts

🗺 Show Meltingpot Indianoceanic Submarine System (METISS) on the interactive cable map

The design capacity of 24 Tbps and the supplier ASN have been repeatedly cited by industry sources, while detailed information on fiber configuration, repeaters, and minimum optical system requirements is contained in the official environmental impact assessment report published by the government of Mauritius.

Why a Dedicated Regional Cable Was Needed

Before METISS, the international connectivity of the islands in the southwestern Indian Ocean relied heavily on a limited set of older submarine systems. One of the main systems was SAFE - South Africa Far East, which was commissioned back in 2002. The METISS project documentation explicitly stated that SAFE was nearing the end of its expected lifespan, and the region required additional capacity and a backup route in case of damage to other cables.

Other factors included the rapid growth of video traffic, mobile internet, cloud services, and the business need for more reliable international connectivity. METISS was designed not only to add capacity but also to reduce the islands' dependence on individual operators and historically established routes. The consortium positioned the system as an open and shared infrastructure capable of enhancing competition in the international capacity market.

Project History

The origins of METISS date back at least to 2012, when the Indian Ocean Commission began promoting the idea of improving regional digital connectivity. The first official cooperation agreement for the project was signed on June 29, 2016, in Antananarivo. It involved operators from Madagascar, Mauritius, and Réunion, who had previously often competed with each other in local markets.

On December 13, 2017, six operators signed an agreement in Port Louis to build and manage the system. The consortium included Telma from Madagascar, CEB Fibernet and Emtel from Mauritius, and Canal+ Telecom, SFR Réunion/SRR, and Zeop from Réunion. This was an unusual model for the region: competing operators pooled investments to build shared submarine infrastructure.

On February 1, 2018, a construction contract was signed with Alcatel Submarine Networks and Italian firm Elettra TLC. ASN was responsible for the submarine telecommunications system, while Elettra specialized in marine operations and cable laying. Early publications anticipated the system's commissioning in 2019, but this timeline was later adjusted.

Various sources estimate the project's cost at approximately €38-40 million to €50 million. Therefore, citing a single definitive figure without access to the consortium's financial reports is inaccurate. The €40 million figure appeared in materials from the contract signing period, while later sources reported approximately €50 million in actual investments. Publications citing €75 million exist but contradict most industry and regional sources.

Construction and Cable Laying

Liquid Telecom was the South African partner for the project. The company provided shore infrastructure, equipment hosting, operational support, and terrestrial transport to operator nodes in the Durban area. The cable lands at Pipeline Beach in the Amanzimtoti/Umbogintwini area, south of Durban, and connects to the neutral data center Teraco DB1.

Marine cable laying began in March 2020. One of the key phases coincided with the initial COVID-19 restrictions, complicating the movement of specialists, coordination of work, and preparation of landing stations. Despite these challenges, the cable was successfully landed at all four points along the route. In Mauritius, the system was brought ashore on June 20, 2020, by the cable-laying vessel Teliri.

After completing the marine portion of the project, terrestrial sections were installed, terminal equipment was connected, optical paths were tested, landing agreements were finalized, and operational teams were prepared. The connection to the terrestrial section in Mauritius was completed on March 1, 2021. Different publications cite March 5 or March 8 as the commercial launch date, so the most precise phrasing is that METISS was commissioned in March 2021.

Route Configuration

The main trunk runs between South Africa and Mauritius. Réunion and Madagascar are connected via submarine branching units. This topology allows a single system to serve multiple island territories without laying separate cables from each island to South Africa.

• Baie du Tombeau, Mauritius - the system's landing point in Mauritius, linked to Emtel's infrastructure.
• Le Port, Réunion - the connection point for the French overseas department.
• Fort Dauphin, Madagascar - the southern landing point, managed by Telma.
• Umbogintwini/Amanzimtoti, South Africa - the connection to Durban's network infrastructure and Teraco data centers.

Coordinates of the points in GeoCables: Fort Dauphin - -25.023, 46.985; Baie du Tombeau - -20.122, 57.495; Le Port - -20.944, 55.303; Umbogintwini - -30.022, 30.902. The names Umbogintwini, Umbogotwini, and Amanzimtoti may appear in different sources to describe the nearby South African landing point and its associated infrastructure.

Capacity and Technical Configuration

The design capacity of METISS is 24 Tbps. This does not necessarily mean that the entire capacity was activated at launch: for submarine systems, design, equipped, activated, and sold capacities are typically distinguished. The design figure represents the system's potential capabilities with the installation of appropriate terminal equipment.

Government project documentation from Mauritius specifies two fiber pairs on the South Africa-Mauritius trunk and four pairs on the branches to Réunion and Madagascar. The requirements also include at least 120 optical channels of 100 Gbps per pair and an initial equipped capacity of no less than 1,000 Gbps. The system includes 32 submarine repeaters, five of which are part of the Réunion branch.

These details require careful interpretation. The wording in the environmental report partially describes minimum requirements and design solutions at the approval stage. They do not provide grounds to assert that every channel was activated at launch or that the configuration has remained unchanged since then.

What METISS Has Changed for the Region

The main advantage of METISS is its direct route to South Africa. Durban and other South African hubs host international operators, traffic exchange points, cloud platforms, and content delivery networks. This allows some island traffic to reach South African infrastructure without a long detour through Europe or Asia. The consortium specifically highlighted improved access to the infrastructure of major content providers located in South Africa.

However, a cable alone does not determine the route of internet packets. Path selection depends on operators' BGP policies, purchased capacity, peering agreements, channel load, and the location of specific servers. Even with METISS, traffic between two connected territories may travel via another cable or a distant transit node.

Latency: Physical Limits and Real Measurements

For a route 3,200 km long, the physical minimum for signal propagation in optical fiber is approximately 31.3 ms RTT. This calculation is based on the speed of light in fiber, about 204,000 km/s: RTT is roughly equal to 2 x 3,200 km / 204,000 km/s, or about 31.4 ms.

This is an idealized limit for traversing the full 3,200 km length. It does not account for terrestrial segments, real route bends, router packet processing, access to the endpoint, or potential traffic deviation to another backbone.

Over the past 30 days, the minimum measured RTT from Baie du Tombeau to Umbogintwini was 48.8 ms. This is approximately 1.56 times higher than the physical limit for the entire system but is plausible for a direct regional route, considering terrestrial segments and network processing. In the reverse direction, the minimum RTT was 50.3 ms, with an average of 53.1 ms.

The direct and reverse directions are nearly symmetrical in terms of minimum RTT: 48.8 ms versus 50.3 ms, a difference of about 1.5 ms. Discrepancies appear only in average values (126.3 ms versus 53.1 ms) and maximums (233.9 ms versus 55.6 ms). This indicates that outliers - such as BGP route changes, temporary detours, congestion, or ICMP processing peculiarities - rather than consistent path differences, create the variance. Thus, the average value of 126.3 ms cannot be considered typical for METISS latency.

Measurements from Minsk, Jerusalem, Singapore, Sydney, and other distant cities, ranging from 212 to 398 ms, reflect the full international route to the Umbogintwini node, not METISS itself. Without traceroute, BGP data, and identification of operator interfaces, it is impossible to prove that a specific ICMP packet even traversed this cable. In the table, these measurements are useful as indicators of node accessibility from various parts of the world but not as metrics for the submarine system.

For the same reason, the floor ratio of 0.714x found in our internal data is erroneous: it compares the minimum RTT of 22.4 ms from Cape Town to Umbogintwini - a South African terrestrial segment that does not pass through METISS - with the physical limit of the entire 3,200 km system. A value below the physical limit is impossible and indicates a comparison of different routes. The correct ratio for the relevant direction Baie du Tombeau - Umbogintwini is 48.8 / 31.3, approximately 1.56x.

Redundancy and Impact of Cable Damage

METISS was designed not only as a source of additional capacity but also as an alternative to existing systems. However, having multiple cables in a country does not guarantee real resilience: an operator must pre-purchase backup capacity, configure BGP policies, and ensure physically independent terrestrial transport to another landing station.

In the event of a trunk segment failure, the impact depends on the location of the fault. A break between South Africa and the nearest branching unit could affect multiple territories simultaneously. Damage to an individual branch could isolate only one landing point from METISS while preserving the operation of other segments. The exact recovery logic also depends on the system's internal architecture and agreements between consortium members.

Repairing a submarine cable involves fault localization, mobilizing a specialized vessel, obtaining permits, retrieving the damaged section from the seabed, installing a new splice, and retesting. The process can take anywhere from a few days to several weeks, depending on weather, depth, fault location, repair vessel availability, and national permissions.

How Critical Is METISS?

METISS is not the sole international cable for Mauritius, Réunion, Madagascar, or South Africa. Nevertheless, it is critically important as a regional route: the system provides geographic diversity, directly connects the islands to South Africa, and reduces reliance on longer intercontinental routes.

Its significance lies not only in its 24 Tbps capacity but also in its topology. METISS has linked several relatively small island markets to a major African network hub through shared infrastructure funded by regional operators. This is a rare example of competing companies collaborating to address the common challenge of digital isolation.

Conclusion

• METISS is an operational regional system approximately 3,200 km long, connecting Mauritius, Réunion, Madagascar, and South Africa.
• The project's history dates back to 2012, with the cooperation agreement signed in 2016 and construction contracted in 2018.
• The cable was commercially commissioned in March 2021.
• The design capacity is 24 Tbps; suppliers were Alcatel Submarine Networks and Elettra TLC.
• Technical details are not entirely confidential: data on fiber pairs, optical channels, and repeaters have been published.
• The minimum measured RTT of 48.8-50.3 ms between Mauritius and South Africa appears realistic relative to the physical limit of approximately 31.3 ms, yielding a ratio of about 1.56x.
• Direct and reverse directions are symmetrical in terms of minimum RTT; average discrepancies are caused by outliers rather than consistent path differences.
• Remote measurements to Umbogintwini cannot automatically be attributed to METISS without route confirmation via traceroute and BGP.