Subsea Cables & Internet Infrastructure

Tabua is part of Google's grand Pacific Initiative, a project to build a mesh-like web of subsea cables connecting Japan, the US, Australia, and many Pacific islands. The islands include Guam, Fiji, Hawaii, and French Polynesia. These islands play a crucial role: they provide power to keep throughput at higher levels than otherwise possible. Another key role for the islands is as telecom switching hubs with each cable landing station serving several high capacity cables.  Tabua is a standard 16 fibre pair spatial division multiplexing cable with two branches landing on the Australian and American sides. Design throughput is 17 Tbps per fibre pair. This dual branch approach has become popular because if the Queensland branch is damaged, traffic can be switched to the New Wales CLS with fibre linking the two cable landing stations. Similarly, on the US side, it lands in Hawaii and also Los Angeles. If the Hawaii/LA segment fails, then the traffic can be routed via other cables landin...

A total of 9 cables land on the beaches near the small town of Bude, UK. There are four operational cable landing stations serving them in the Bude, UK area: two Vodafone CLS, a Colt (former Lumen) CLS, and a BT facility. Please click on https://lnkd.in/gGAP3QMA for a plethora of photos of the cable landing stations. The map illustrates the tendency for telecommunications networks to lack adequate physical diversity to ensure resiliency. Sometimes a laissez faire regulation is not the right approach. Most back haul fibre from the cable landing stations to London probably traverses the single road parallel to the beaches. See below.  When I worked at Hibernia Atlantic as an exclusive sales contractor, we cited the concentration of cables at Highbridge and Bude as good reasons to purchase capacity on the Hibernia North & South cables. North lands several hundred kilometers above Cornwall and at Halifax on the North American side. It was a compelling sales ptich. These cables toda...

Meta's Anjana cable sets an Atlantic bandwidth record with 24 fibre pairs each transmitting 20 terabits per second for a total of nearly a half petabit. This huge capacity reflects its spatial division multiplexing (SDM) design. Traditional subsea cable designs maximize capacity per pair, but this leads to nonlinear signal distortions once a threshold is exceeded. Hence additional power to boost the rate above the threshold yields only small gains. This inefficient use of power limits fiber pair counts to 8 or less per cable with most cables rarely exceeding 150 Tbps. In contast, SDM increases the total bandwidth punch by operating each pair at lower transmission rates to avoid these nonlinear signal distortions. In turn, the lower transmission rates free up power to support enough more pairs to sharply raise total cable throughput, which ranges from 200 Tbps to a half petabit per second.  Another notable feature of Anjana is that it lands at Myrtle Beach, South Carolina, and Santa...