We are more connected than we think

A quick overview of submarine communications cable systems in the Caribbean.

chain link by adamr (FreeDigitalPhotos.net)In the past few weeks, Cuba commenced transmissions to the Internet on the ALBA-1 submarine cable, which runs between Cuba and Venezuela, and has a landing point Jamaica. Although there is generally much to rejoice whenever a new cable is commissioned, it was more so the case with Cuba, since the ALBA-1 is its first. Although most of us in the Caribbean might know that submarine communications cables are used in the region to provide international (or extra-territorial) connectivity – to the Internet and other international gateways – we might not truly appreciate how connected we are.

So how connected are we?

TeleGeography maintains a free interactive map of active and planned submarine communications cable installations worldwide. The data used is from Global Bandwidth Research Service, a TeleGeography property, and is updated regularly – the most recent was 31 January 2013. Figure 1 is an excerpt of the global map and shows submarine cables and their landing points around the Caribbean basin. The cables shown have a maximum upgradeable capacity of at least 5 Gbps (or 5,000 Mbps).

Figure 1: Excerpt from TeleGeography’s global submarine cable map showing the Caribbean region (Source: TeleGeography)

There are at least 15 independent submarine cables connecting Caribbean/CARICOM countries

  • The most heavily connected is Puerto Rico, which has approximately nine landed cables
  • The least heavily connected are Cuba, Guyana and the Turks and Caicos Islands, which each have one cable landed
  • British Virgin islands, Dominican Republic and Puerto Rico are three important concentration points for telecoms traffic in the region. Traffic from a number of countries tends to get routed to one of those three countries, and then is routed out of the region to North America.

Table 1 provides a quick summary of the number of submarine cables or landing points in individual Caribbean countries.

Table 1:  Number of submarine cables or landing points in select Caribbean countries (Source (TeleGeography)
Table 1: Number of submarine cables or landing points in select Caribbean countries (Source (TeleGeography)

As is, Figure 1 can be quite overwhelming. Table 2 highlights a few of the important submarine cables in the English-speaking Caribbean

Table 2:  Details on select submarine cables in the Caribbean (Source; TeleGeography)
Table 2: Details on select submarine cables in the Caribbean (Source; TeleGeography)

A few additional things to know…

1.  Similar to fibre optic cables on land, submarine cables are expensive to deploy; hence many developing countries tend to rely on wireless, especially satellite, solutions to provide international connectivity. However, wireless services can be expensive for consumers, have speed limitations, and for voice and Internet services in particular, the time delay in reception, due to distance, can result in poor service quality. On the other hand, once submarine cables are deployed, they tend to be more cost-effective and reliable on major routes.

2.  Cables can be broken.  Fishing trawlers, anchors, earthquakes, turbidity currents among other things, are typical culprits. You may recall that the 2010 earthquake in Haiti had damaged the submarine cable systems to that country. In the aftermath of the disaster, one of the first order of business was to re-establish connectivity, which in the first instance, was achieved via satellite and other wireless solutions.

3.  According to the International Cable Protection Committee, the following international treaties protect submarine cables:

  • The International Convention for the Protection of Submarine Cables (1884)
  • The Geneva Conventions of the Continental Shelf and High Seas (1958)
  • The United Nations Convention on Law of the Sea (1982)

4.  Transmission speeds on submarine cables are dependent on, among other things, the condition of the cable, the distance being covered and the equipment connected to the cable.

As of 2012, operators had “successfully demonstrated long-term, error-free transmission at 100 Gbps across Atlantic Ocean” routes of up to 6000 km, meaning a typical cable can move tens of Terabits per second overseas. Speeds improved rapidly in the last few years, with 40 Gbit/s having been offered on that route only three years earlier in August 2009… (Source: Twisted Sifter)

5.  Finally, most submarine cable systems are owned by a consortia of telecoms companies, with the bandwidth being shared by the members. Hence no one entity is likely to have access to all of the capacity of a cable, which could be up to 2.1 Tbps (Terabits per second), in the case of the GCN system in the eastern Caribbean. Typically, the cable systems are designed with large excess capacity to accommodate for growth, but initially, only the capacity that is needed is brought into operation.


Image credit:  adamr / FreeDigitalPhotos.net



  • Hey ya,
    Interesting stats. Didn’t realise Jamaica was now at 5. Good going or is it? It is great to see that the Caribbean is wholly connected with reliable media. Keep up the good work.

    • Thanks Monie!

      It is why I had written the article. Many of us might know that our respective countries have submarine cable connectivity, but we might not realise how extensive those networks actually are in the Caribbean…

  • Hi Michelle:
    Reference this sentence “The cables shown have a maximum upgradeable capacity of at least 5 Gbps (or 5,000 Mbps).” Did you mean to say ‘T” as in terabytes? Because that number seems a bit low for upgradeable capacity for all cable systems shown.

    The usual capacity references are to ‘design’ and ‘initial’ (or lit) capacities. For example, The East-West system with its Morant Point (Jamaica) landing has a design capacity of 720 Gb/s and is now initially set at 120 Gb/s.


    • Carlton,

      Honestly, I checked and doubled-checked, as I did think it might have been a mistake, but TeleGeography states in its introduction to the map:

      “Cables shown include international and US domestic submarine cables with a maximum upgradeable capacity of at least 5 Gbps.”

      In using this qualifying criterion, I can only guess that a more comprehensive map has been developed, and there might indeed be submarine cable systems that have been excluded because they did not satisfy that minimum capacity.


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