Posts

Showing posts with the label beach manhole

Introductory Schematic of Subsea Cable Architecture

Image
1. The submarine line termination equipment, consisting of active electronics and transponders (lasers and optical receivers), was traditionally kept at the cable landing station. This began changing when carriers wanted to own and manage their own dedicated capacity (fibre pair or spectrum slice). Telekom Malaysia was an early example. It took two fibre pairs on the ASE cable as opposed to a fraction of the consortium lit capacity. Later the hyperscalers crystallized this evolution in the open cable model which limits common ownership to the wet segments. Each owner has either fibre pairs or spectrum and makes its own decisions concerning where to place the SLTEs. Because cable landing stations are not designed as large carrier neutral interconnection points, the SLTEs are almost always housed in a cage at a carrier netural data center. It is this flexibility in choice of location and equipment vendor that makes the open cable model so appealing. It also facilitates hyperscalers build...

SubOptic 2025 Presentation: Subsea Cable Transmission - Part 1

Image
Benoit Kowalski gave the presentation at the event. The diagram below shows the standard subsea network architecture. The fibre optic cable and optical amplifiers are collectively called the wet segment. The rule of thumb is to bury the cable in waters a thousand meters or less deep. Approaching shore one has a choice. One can give bring the cable ashore using small boats. The cable initially lies exposed on the beach up to the beach manhole. Then the cable is buried from some point in the water up to the manhole where it is spliced into the front haul fibre that carries the signal to the cable landing station. From the CLS back haul fibre goes to a carrier neutral data center that serves as a point of presence (POP) or interconnection point. The other platinum-plated approach uses horizontal drilling to install a bore pipe from the manhole to a point on the sea floor offshore. This is much more expensive, but better protects the cable.  A couple of things to note. I...