Can't be dolphins at that depth.
Or sharks. Must be radicalized angler fish.
SEA-ME-WE 3 is a marvel: the 39,000km submarine cable connects 31 nations, has 39 landing stations and stretches from Germany to Japan. Its two fibre pairs each carry 480 Gbits/s, a decent slice of the world's data traffic. But right now the cable's not at its best because the spur between Jakarta and Singapore looks to have …
This is one excellent reason why anyone going 'cloud' really needs to look at locally-hosted options. There's now a local presence for Azure but I don't think Office 365 is being hosted here currently. (Anyone know?)
You can also spin up EC2 instances in Amazon's local DC and Salesforce likewise has local instances but what about all the SaaS offerings running on top of these services - are these all run from local DCs?
Moving to the cloud does remove one part of the IT concern but the idea that you can just trust it blindly is of course foolish. I have seen people sign up to services and migrate all their data in - at significant expense and then only afterwards find that all their data is actually in another country and the latency is less than stellar.
What the fuck do you expect from beancounters??
All they know is how to
save money enlarge the executive bonus pool. They could care squat about such "techy" things like latency, and resiliency, until they hit a slowdown loading Failbook or Twatter.
THEN they are all over your ass!
"The `internet` is slow."
Is it Beer O'Clock yet???
Typically if the location of the fault is "known", they use big grappling hooks to drag the cable to the surface up to the cable repair ship, then splice the ends in the on board clean room, test and sent it back down.
If the amplifier has gone faulty, they have to send down an rov to cut the cable first, and then drag up the ends to fix and splice the cable.
Added to the fact that you have to get a specialist cable repair ship first to the scene (check up the stupid situation that Indonesia pulled recently about only using a locally flagged vessel), then find the cable on the sea bed, then there are multiple layers of protection on the cable itself and usually around 10,000V too on the power supply wire, as you need to power those amplifiers somehow, its not as simple as a choc block and some heat shrink bodge.
Lab icon, as clean room required to fix it.
Pretty much correct, only they drag up one end of the cut cable to a position at least the depth of water away from the break, splice in a new section, then move twice the depth of water and drag up the other end at aposition at least the depth of water away from the break, and splice that broken end to the new section.
The new section will be quite long, at least three times the depth of water, and once it is lowered into place there will be a loop of loose cable on the seabed.
If they tried to raise a cable in the middle without cutting it it would break when being lifted, the added tension would be far above the capability of the cable.
When being laid a part of the cable which starts at position x at the surface then falls in a curve into a position on the seabed some distance away from x.
Sorry if that's not clear, a diagram would make it easy to understand, but describing it in words is trickier.
where the cables were so intertwined that you never removed an old cable, for fear of damaging the other cables
My nightmare is to crawl through the cable mass, trying to find the exit, with only a glowstick as aid.
Maybe Junji Ito has done a work on sysops....
Well, the oceans are pretty big. Actually, they're really, really, really HUGE. So, the chance of two cables crossing anywhere near a break is pretty small. It's not really quite so bad as some of the area under the raised floor of some of the old mainframe computer rooms, where the cables were so intertwined that you never removed an old cable, for fear of damaging the other cables (Snakes! They look like snakes!).
Most of the breaks seem to happen near shore anyway, usually where some drunken ship's captain has dropped anchor on top of a cable, or snagged one. Out in the open ocean, away from the continental shelves, the cables are usually so deep that anchors and such can't reach then (You won't find a ship with an anchor chain much longer than a few hundred feet at most.).
There may be some breaks due to undersea boulders falling off of undersea cliffs and landing on the cable, but those tend to be somewhat rare. There may also be some where the cable is stressed as it crosses an undersea rift of cliff, but, again, those are pretty rare, too. In past times, there were some incidents of sea-life trying to eat the cables, but most modern cables are pretty resistant to that. More likely, though, is that a cable may have swayed in the current, and abraded itself against a hard, sharp object, which has damaged the cladding/insulation/etc. Once sea water has leaked inside, all sorts of bad things can happen, especially given the voltages involved (e.g., electrolytic corrosion), as well as damaging the fiber itself (Water does nasty things to glass fibers, via Hydrogen/Hydroxide contamination.).
Or, something like that.
P.S. I'm afraid we have more to fear from the bunglings of the incompetents, than from the machinations of the truly evil.
Easy. You fill in "Under Ocean Fibre Cable Fault" (form E3.7) and it gets repaired by the fibre optic fairies. Just don't complete section one as "Nature of fault: iPlayer keeps giving the roundy-roundy thing, suspect under ocean fibre fault ..."
Since the widespread use of GPS cable routes are very accurately known and cable and pipeline crossing points have to be determined and negotiated when a new cable is laid.
Especially on continental shelves where (down to about 1000m water depth - sometimes deeper) they are armoured cable and typically laid in a ploughed trench 1-2m deep on the seabed. The major damage hazard at these depths is by trawl boards as fishermen trawl for weirder and weirder fish at greater depths.
You really don't want someone ploughing through your cable (or pipeline) when laying a new one. because of this danger, cable crossings are very carefully planned and engineered, usually achieved by stopping the plough 1-2 km back from the the crossing site, surface laying the new cable over the cable to be crossed, then retro burying it using powerful water jets on a ROV. Sometimes gravel is dumped over the crossing site to give additional protection.
In shallower waters as another commenter said it may be dragging anchors. That may required deeper burial and double armoured cable The worst possible place is where supertankers or large container ships anchor nera cable landing points- especially Singapore and HK harbours Singapore has its own specialised burial barge permanently stationed there which can bury up to 20m deep!
Less common hazards are cables wearing through by "thrumming" over exposed rock surfaces in seabed level currents (rare and try to avoid these hazards when planning cable routes) and cable breaks by slumping in undersea landslips sometimes triggered by earthquake activity ( gain avoid laying across steep slopes )
Early deep sea cables in the Atlantic were sometimes attacked by deep sea sharks (Goblin Shark) with an electric sense - the field caused by the power cable that feeds the repeaters looked to the shark like a big meal. All cables since about 1988 include an aluminium tape "screen" layer to shield this field
I heard a story from a guy that used to be part of a cable laying crew.
The ship would follow the direction chosen by the ROV on the sea bed so if he diverted round something the big floating drum above followed. One day the captain arrived at the ROV control room (a converted shipping container welded to the deck for the duration) using colourful words and something along the lines of "why have we been going in circles for two hours!?", turns out a tin box stuck to a deck can get pretty hot and stuffy and the ROV guy and his mates can doze off.
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