Subsea Cables & Internet Infrastructure

Amazon's North American fibre optic network below. Its global network consists of nine million kilometers of owned fibre pairs. Amazon spent the last year experimenting with hollow core fibre and is now ready to join Microsoft in long haul deployments. See their blog for more setails:  https://aws.amazon.com/blogs/aws-insights/building-resilience-inside-awss-nine-million-kilometers-of-fiber-optic-cabling/. Microsoft has deployed hollow core fibre in the long haul to connect three AI data centres. It owns the leading hollow core manufacturer and research company, Lumenisity.  New hollow core designs unveiled in a recent Nature Photonics paper have solved the main obstacle to long haul deployment, namely high attenuation. High attenuation simply means light pulses fade rapidly and hence require frequent amplification. In contrast, Luminisity's new hollow core design unveiled in the Nature publication has 50% less attenuation than standard fibre. This means it can be incorpor...

At the beginning of the third millennium almost all Trans-Atlantic cables directly linked the US or Canada to either Ireland or the UK. Flag North landed at Northport, New York, and Bude, UK. Hibernia North (EXA North) was a rare exception. It came ashore at Halifax and also in Southport, UK. Yellow touched ground on Long Island and at Bude. AC2 came ashore also at Brookhaven and Bude. Hibernia South (EXA South) landed in Halifax and also at Dublin. Finally, Apollo North touched ground at Brookhaven and Bude. Clearly this is inadequate physical diversity in terms of landing points and cable landing stations. It is highly cost effective because subsea cables can share common terrestrial infrastructure, but cost and resiliency are sworn enemies. There is almost always a tradeoff. Almost all Trans-Atlantic traffic went to the 9th floor Telx facility at 60 Hudson and the 111 8th Avenue data centre in Manhattan. In London the destination was almost invariably the Telehouse North and East da...

Eastern Light is building a hybrid subsea-terrestrial dark fibre ring connecting Sweden, Finland, the Baltics, Germany, Denmark, and Norway. This morning I interviewed their sales director to better understand this ambitious project. The fibre pair count is 3x 144 pairs or 432 in total. No lit optical circuits or wavelengths will be sold. Instead, customers will be leasing or purchasing via IRU fibre pairs that they will light using their own equipment. There are ILAs for the subsea spans located   on islands, but the short distances make them an option, not a necessity. However, some customers will undoubtedly prefer buying less and optically amplifying to juice the transmission rates. Because it is a dark fibre network, the customer base will be predominantly hyperscalers, big carriers including the incumbents (Telia's international network is old), university research consortiums, governments including their national militaries, NATO, and banks. In particular, hyperscalers are e...

Technology: Spatial division multiplexing.  Fibre Pairs: 12.  Founding Father: Google Consortium Members: Google & Orange. The French PTT is best described as a junior partner.  RFS: January, 2021.  Route: Direct Ashburn Equinix to Paris. Landings: Virginia Beach, VA. Saint-Hillaire-de-Riez.  Notable Features: Second cable after Marea to directly link Ashburn Equinix to Europe. Dunant was first subsea network  in the world to deploy spatial division multiplexing and and achieve a two digit fibre pair count.  Dunant was the beginning of the spatial division multiplexing revolution. It was the first cable to leapfrog from the standard 4 to 8 fibre pair coherent optics paradigm for the Atlantic to the 12 to 32 pair spatial division multiplexing model that dominates today. Dunant went live January 19, 2021 with 12 fibre pairs and lit capacity of 250 terabits per second. However, the design capacity was even higher, 300 Tbps. The cable is named after t...