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Showing posts with the label resiliency.

Bude, UK Subsea Cable Landscape & Resiliency Concerns

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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...

Anjana: The Atlantic's New Leviathan

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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...