Subsea Cables & Internet Infrastructure

A. Three cables have lost their Dubai connectivity: EIG, TATA Gulf, and IMEWE. EIG is depicted in the top panel. It goes as far West as London. IMEWE lands at Marseille. Finally, TATA Gulf is a branch of TGN-EA. B. EIG uses a branching unit to split into a subsidiary trunk that goes up the Persian gulf and a main trunk to Europe. Hence the main trunk is probably ok. The same comment applies to TGN-EA and IMEWE.

 A point: Lisbon Equinix (LS1). Z point: MDXI, Server House or Medaillion facilities. Term: 1 Year. Cross connects not included.

***Hong Kong/Tokyo, Tokyo/Taipei, and Hong Kong/Taipei. ***Outages started 10:14 GMT, July 6th, 2025. ***Until a cable ship can investigate, no idea of the cause. ***I caution the paranoids among you to refrain from speculation. Hong Kong is part of China so the sabotage theory is most likely bogus. *** The graph shows that the common factor among these segments is Taipei.

Google's SOL cable is the first Trans-Atlantic network to connect Florida to Europe with a landing at the Telxius Santander CLS on the Northern Spanish coast. The other cable, Nuvem, announced some time ago, will link the Myrtle Beach, South Carolina CLS owned and operated by DC BLOX to a landing near Lisbon. Details are sparse regarding SOL, but it will probably be similar in performance and design to the 16 fibre pair Nuvem cable that clocks 384 Tbps. The Florida landing is in the Palm Coast area between Jacksonville and Orlando. An interesting feature is that both cables do island hopping. Both cables land in Bermuda and Azores (where a US Air Force base is located). Island hopping serves three goals. The first is power to offset voltage drop. Intermediate power feeding en route improves throughput. The more often a cable can feed, the higher the bandwidth. The other factor is optical amplifier noise. Amplification introduces noise which accumulates from amplifier to amplifier. ...

Each fibre strand consists of the core and the cladding. The core is like a one way road for the light to traveland cladding are the guardrails that prevent it from escaping. The refractive index measures how fast light traverses a given medium. It is defined as the ratio of the speed of light in a vacuum to the velocity of light via the medium. The core has a higher refractive index than the cladding. As long as the refractive index differential is large enough, photons that hit the cladding at a critical angle or less will bounce back into the core. Physicists call this bouncing of light internal reflection. So the core/cladding structure is designed to preserve the optical power or amplitude of the wavelengths. It minimizes optical attenuation, the great enemy of optical networking along with chromatic and polar dispersion.  The bottom middle chart shows that optical attenuation, which reflects opposing forces, reaches a minimum in the C band. The C band is defined as wavelength...

 2Africa; Senegal/Portugal; 100G; $18.5K; 2 Years. WACS; Ivory Coast/Portugal; 10G; $8,250; 3 Years. 2Africa; Nigeria/South Africa; 100G; $24,750; 1 Year. Equiano; Nigeria/South Africa; 100G; $20K; 1 Year. Equiano; Nigeria/Portugal; 100G; $19.5K; 2 Year. 2Africa; Ghana/Nigeria; 100G; $23.5K; 1 Year. 2Africa; Ivory Coast/Portugal; 10G; $10,500; 1 Year. 2Africa; Ivory Coast/Portugal; 100G; $33.5K; 3 Year. Remarks: 2Africa CLS cross connects are $150 max. WACS cross connect charges are five digit.

Dr Kowalski is a Nokia employee who collaborates with ASN. His presentation on the first day of the conference is a good subsea cable primer.  The transmission equipment is known as the submarine line termination equipment or SLTE. It has three key components. Encoding involves taking the digital input and converting it into a series of laser commands according to the modulation scheme. FEC or forward error correction adds redundant bits called parity bits that help the far end FEC to detect and correct payload mistakes. It is a bit like a router creating the checksum field in the IP packet header. Once quality is control is completed, the laser sends the optical signal. Its ever weakening light travels the fibre until it is passively boosted by erbium doped fibre in the amplifier that has been raised to a high energy level by pump lasers. At the far end of the linear transmission the steps are reversed. The optical receiver takes the light signal and converts it into the appropria...

There are a large number of desperately poor African states below Senegal and above Cote d'Ivoire on the West African Coast that have access to only one or no submarine cables. These nations include Liberia, Sierra Leone, Guinea, Guinea-Bissau, and the Gambia. Landlocked countries that would benefit from more subsea capacity adjacent to these coastal states include Mali and Burkino Faso.  Right now their main bandwidth supplier is ACE, which lands in all the listed coastal states. ACE is ASN's problem child. The kid that is always getting into trouble. It has a reputation for outages and network disruptions. The cable landing station operators in general hold the cable hostage. In Sénégal Orange manages the facility, charges high cross connects fees, and hence has a quasi-monopoly on its capacity. Similar problems bedevil ACE cable landing stations in general. In some countries an ISP consortium manages the cable landings, but abuse still occurs. In Sierra Leone, the government...

Rumors have been floating around for several months about a successor project to AAE1 known as AAE2. Like AAE1, the key goal is to connect Hong Kong and Singapore to India, the Middle East, and Europe. The core consortium includes PCCW, Telecom Egypt, Omantel, and Sparkle. Just like other recent projects such as SMW6, AAE2 will avoid the Red Sea. Instead, the cable will land in Oman, then traverse Saudi Arabia and Egypt to reach the Red Sea. I applaud the cable's designers for ditching the Red Sea. It was long overdue. However, a more logical approach is to avoid Egypt all together. The Saudi Arabian desert will be expensive. The consortium has increased both capex and opex further by using Egypt for transit. Egypt treats subsea cables the way a toll road treats cars. It extracts a monopoly fee from them. It makes no sense given that Israel has a competitive telecom market versus Egypt's pseudo competitive market.  Another interesting design feature is that Italy was mentioned ...

The three fibre pair Quintillion cable went live in 2017. Its current throughput is 10 Tbps per fibre pair. It includes terrestrial back haul from Prudhoe Bay down to Fairbank, Alaska, in the middle of the state. The cable was deeply buried with an average depth of 3.7 meters with bore pipes used to bring the fibre pair ashore to the manhole. Each landing threads the fibre optic cable through steel conduit at least 18 meters under the sea floor up to 1.6 kilometers offshore. This was accomplished via horizontal directional drilling. Project cost was around $150 million. The cable is a godsend for these Alaskan communities and was built to top notch engineering standards. But it still suffers from ice scouring incidents where icebergs cut through the sea floor and have severed or severely damaged the cable. A major outage occurs roughly once a year, but the real problem is the repair time. It is simply not economical for a subsea cable to own an icebreaker or to risk a cable ship's ...

Juno is the Queen of the Olympian gods in Roman Mythology. This 20 fibre pair cable has design capacity of 320 Tbps, which makes it the highest capacity subsea network to connect the US to Asia. It lands at Grover Beach, California, and also has Japanese landings at Shima and Minami-Boso. NTT is the project's main backer and owner. The carrier clearly felt that two Japanese branches along with three cable landing stations (Softbank Maruyama, NTT Shima, and NTT Minami-Boso) would significantly improve resiliency given Japan's reputation for earthquakes and other natural disasters such as tsunamis. As is usual for a NTT project, it created a standalone company known as SerenJuno in which it has majority ownership to minimize risk. This way any misfortunes would not result in the parent company having financial liabilities. NTT is also extremely reserved about revealing capacity owners on the system. I have learned that PCCW is on the system. Details Ownership: NTT and Mitsui. Cap...

In a recent interview META subsea engineers suggested their next project would be a 1 Petabit Trans-Atlantic cable. They pointed to three possible ways of accomplishing it: multicore fibre, use of the C and L spectrum bands, and 50 fibre pair SDM. Pros and Cons 1. Multicore is subject to cross talk. Right now the only multicore cable is the Taiwan-Phillipines-US cable scheduled to go live this year. A Google project with NEC as the vendor, it has two cores per fibre strand and 26 Tbps total per fibre strand or 13 Tbps per core. The challenge is cross talk. The light spills from one core to the other and vice versa. Obviously this distorts the signals and at high transmission rates the distortions become greater and greater and the signal-to-noise ratio disintegrates. The advantage of multicore fibre is that no redesigning of the optical amplifiers is required. Since everyone acknowledges that SDM alone is unlikely to surpass the half terabit mark, Google is obviously interested in mult...

Picture below shows subsea amplfiers aboard a cable ship. They cost roughly $250K a piece, can support up to 40 Tbps, and are spaced every 70 kilometers or 42 US miles. These remarks apply to these specific amplifiers. As noted in Part 1 of this series, erbium doped fibre eliminated optical-electrical-optical (OEO) conversions for amplifiers. So the limiting factor of computer hardware involved in the conversions was eliminated. The result was a 'transparent' technology that placed no limits on submarine termination equipment upgrades. Subsea cables became highly scable because the amplifiers could easily handle higher throughput achieved via DWDM improvements. These amplifiers are tough buggers. They must withstand severe pressure at depths as great 8,000 meters for 25 years as well as nasty seawater corrosion. The amplifier hull is generally made of titanium or a special beryllium copper alloy, C17200, which conducts heat and electricity very well and is highly resistant to ...

Facebook engineers during an interview on the Waterworth project provided details about their next big project. 1. Facebook is planning to build the first one petabit per second Atlantic cable. No details yet available on end points. Given traffic flows it is most likely to directly connect Continental Europe and the US. 2. META engineering is looking at three options to achieve one petabit per second throughput. A. Using both the C and L spectrum. This would effectively double the bandwidth. B. Cable will definitely be SDM (spatial division multiplexing). Strong likelihood that will be 48 pairs. C. Another possibility is two core optical fibre in order to double the bandwidth per pair. 3. I believe the most likely option is using C and L bandwidth. Arelion has incorporated L band spectrum into its DWDM Layer 1 service between Atlanta data centers and Ashburn Equinix using Infinera gear. Colt and Sparkle have used the L band on terrestrial routes. Most DWDM equipment today offers both ...

1. The Waterworth cable will link the US to South Africa with a branching unit to Brazil. It extends from South Africa to India & onto to the Pacific and the US. The total length is greater than the Earth's circumference at approximately 50,000 kilometers. 2. Subsea cable projects are taking 3 to 5 years from initial idea to commercial service. 3. US traffic goes to Europe. It's aggregated with European originated traffic and then traverses the Mediterranean Sea to reach Egypt and takes terrestrial routes (Telecom Egypt) to the Red Sea. Then the traffic flows down the Red Sea. From there it either heads to India or bypasses it with Southeast Asia being the destination. 4. In the eyes of Facebook's subsea engineering team, the standard cable routing described above creates a host of problems. First of all , the Red Sea is a single point of failure. Same holds for Egypt. Secondly, the Mediterranean Sea requires many government permits as cables inevitably goes through ter...

First Point: The Portugal and Spanish grids are tightly integrated with limited power connector to the rest of Europe. Solar and wind play a big role and both power sources suffer from what is known as frequency instability. Solar and wind generated power is much more volatile than traditional power sources. Traditional power generators have angular momentum inertia. It takes a while to up or lower the power due to the inertia in the spinning components. A natural gas turbine takes a few minutes to spin up. A nuclear reactor an hour to lower or increase output by 10% (French reactors do load following). Solar and wind create very volatile power fluctuations that can easily trigger a circuit breaker. In an isolated grid if a circuit breaker is triggered, the power in the remaining active part of the grid increases. This triggers more circuit breakers and usually brings down the entire grid. 2. The consequence of the first point is that avoiding a repeat of the Iberian Penisula outage re...

`This article reflects discussions I have had with war planners, government officials, policy analysts, and subsea cable colleagues.  1. A striking fact is that there is no compelling evidence of subsea cable outages due to sabotage since the end of WWII. Subsea cables are poor terrorism targets. Terrorists create terror by killing and maiming people and damaging highly visible and important infrastructure like bridges, skyscrapers, prominent buildings or sites having symbolic importance. Intentional damage of a thin cable buried two meters deep in the English Channel does not have the shock value or cause sufficient disruption by itself to justify the great effort of clandestinely locating and severing it. Secondly, there are so many cables now that sabotage of one or two has little impact on voice or data traffic. RIPE analysis indicated that a country like Estonia experienced little layer 3 degradation despite losing subsea cables landing in the country or adjacent Finland, a r...

I've been in telecom since 1992. This qualifies me as an 'old fart' or 'dinosaur fossil' as American teenagers would say. This means I've seen every mistake made by subsea cable capacity owners. 1. Buying lots of capacity between cable landing stations, but owning no fibre from the CLS to the customers' destinations, namely the popular carrier neutral data centers. You can't be competitive if you must buy 100G or 400G metro waves from a UK landing station to Slough Equinix. Lease a dark fibre pair ring and light it with DWDM. Don't be penny wise and pound foolish. Those network investments will dramatically improve operating margins. The amazing thing is that PPT members of cable consortiums make this mistake all the time. If it is worth spending $55 million for an undersea fibre pair, then it is worth adding a couple million to the pot for back haul IRUs. 2. Refusing to extend the network to new locations unless the order achieves an investment thre...

The conflict between China and the West is exacerbating bandwidth shortages on key routes like Marseille to Singapore. AAE1 is maxed out just like SWM5. Both will be upgraded this year, but I believe all the incremental capacity will be snatched up even before upgrades are finished and the capacity delivered to customers. Furthermore, China Unicom is the lead AAE1 consortium member with China Mobile also selling capacity on the system. Avoiding carriers incorporated in China makes intercontinental capacity shopping is an excruciating exercise. I've been seeking Express AAE1 100G for almost a year for clients for whom China is a red line. Bandwidth sourcing has become a marathon. 😄 In light of this, I recommend buyers consider Peace despite the fact that it is a Chinese financed project. Encryption does work. It will not protect the IP overhead, which include the IP addresses, but the data payload itself will remain safe. Moreover, there are Peace providers such as PCCW or TELIN t...

What most people don't realize is that the following cables have not threaded the Red Sea yet due to the threat of Houthi missile attacks: 1. 2Africa. 2. Africa-1. 3. Blue Raman. 4. IEX. 5. SWM6. It is likely that none of these cables go live this year (2Africa Marseille/Mombasa segment among others ). When I ask industry insiders whether the Red Sea segments for these cables are finished, I get the roar of silence. The impending capacity drought reflects the failure of subsea cable designers and senior carrier management to take seriously their over-reliance on the Red Sea. Even Blue-Raman, which bypasses Egypt, traverses the Red Sea before landing near the Jordanian Aqaba data center. It is time for the telecom industry to work with Saudi Arabia to build routes that completely bypass the Red Sea and hit water on Israel's coast. Even it means neglecting Djibouti. Carrier culture is not innovative. Never has been. Technology comes from the network vendors like Ciena or Infinera...