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120 Gigabit Pipe To Oz Begins Operation
dustpuppy writes: "The new Southern Cross Cable Network connecting Australia to the US is now operational. Featuring 120 Gigabit capacity and with a latency of 70 msec, the new trans-Pacific cable is 120 times the capacity of the existing Australasia/North America connection. Now us poor Aussies can download our mp3s that much faster! You can read more about it here." Interesting, too, how it's constructed. From the article: "The network consisted of two separate cables configured in three self-healing rings, with all three rings to be completed early next year. The duplicate-ring construction gave the network greater redundancy - if one side of the network was damaged or became inoperable, traffic could be transferred to the other side instantly." Neat.
Yes, but how big are these mp3s? Are these punk mp3s? Leonard Cohen mp3s? =)
But then it's like most (usually lying) women say: "it doesn't matter how big the mp3 is, only how long you can maintain your connection."
end communication
While I'm here, someone mentioned that 70ms is pretty slow for this type of connection - which amazes me, because it blew me away that they could get it that low. (remember, we're talking 1 direction latency here - not ping times, which would atleast be double)
A quick calculation:
A quick check of the net tells me that the distance from Sydney (where the cable is landed in .au) to Los Angeles is 7487 miles (according to a travel agent flight distance site - who knows?), or about 11979km. (pretty similar to the diameter of the earth, which is 12742km)
The speed of light is roughly 299,792,458 m/s so, the best (according to current physics :/) time we can do is about:
39.957 milliseconds
Just at the speed of light we lose almost 40ms, then they've gotta switch it at several points along the way, and while optical switches EXIST, it seems unlikely they're doing optical switching yet.
All in all I reckon the 70ms figure is AMAZING..
I've been a nerd nearly all my life, but it still floors me to think that it takes longer for information carried by sound to travel between two people yelling to each other from opposite ends of a stadium in Sydney than it does for information carried by the Net to travel between two people chatting from opposite sides of the globe...anybody else feel this way?
I'm not sure about the Pacific floor, but I know the Atlantic floor is expanding -- so this applies to trans-Atlantic cables at the veyr least.
As the plates expand at the rate of [inces/feet?] per year, what happens to the cables? Is the growth small enough that the cables won't stretch to a critical frailty until after they've outlived their usefulness?
The bandwidth has nothing to do with latency. Even if it were going at the speed of light, there'd be latency issues when going halfway around the globe. 7 ms, as you suggest, is faster than it would take light to travel the same distance.
A map of Australia's links to the US and the rest of the word is here.
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