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Geography Is Destiny: Telegraph Cables Circa 1922

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Looks very similar in design to our present fibre optic subsea cable networks. For example, the Red Sea is a telegraph cable highway and Singapore is a telegraph cable hub. However, the Persian Gulf is not important because hydrocarbons won't be discovered there for another 30 years. Note the cable connecting South Africa to Australia, which is reminiscent of Google's Umoja cable. Note the cables connecting Argentina and Brazil to Senegal and South Africa, but Nigeria, a major hub today, has no connectivity.

Anatomy Of A Deep Sea Fibre Optic Cable

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On the left is a deep sea fibre optic cable. It consists of fibre pairs, ranging from two to 24, placed in a hermetically sealed stainless steel chamber surrounded by closely packed steel wires, then a copper power conductor layer, and finally a polyethylene sheath. The diameter is usually just 17 millimeters or 1.7 centimeters. A standard home garden hose in the US is about 16 mm. Deep sea cables must be thin because the cable's length can be as much as 12,000 kilometers. It would be very difficult to transport and lay a thick cable over long distances. Deep sea cables have always been thin. The engineering challenge is to make it thin and highly reliable.  Note that in shallow waters, usually defined as either 2,000 or 1,000 meters deep and less, the cables may have external armor in the form of steel wires wrapped around the polyethylene sheath. This protects against fishing and anchors. The cable sample on the right is armored. An armored cable typically has one to three sets o...

More Routing Details On Facebook's W Cable

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It is important to keep in mind that the Facebook's W cable design is not finished. But reliable sources suggest it will originate at a Georgia or South Carolina CLS and first land in Nigeria. From there the cable will go to South Africa with a POP probably at the Cape Town Terraco campus. Then it sails for Kenya and up from Kenya to Oman before landing at Mumbai. Oman is becoming an important telecom hub with Ooredoo hosting the 2Africa CLS and lower connectivity costs than the UAE. I would not be surprised if Ooredoo also hosts W as well. By the way, branching units may be a better way to incorporate more countries into this cable network. Yes, my hands are not steady. I got Cs in Art in high school. 😀