Per un ingegnere come me,
articoli come questi sono emozionanti :-)

juan carlos

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How the Internet works: Submarine fibre, brains in jars, and coaxial cables

A deep dive into Internet infrastructure, plus a rare visit to a subsea cable landing site.

by Bob Dormon - May 24, 2016 9:57am CEST

Ah, there you are. That didn't take too long, surely? Just a click or a tap and, if you’ve some 21st century connectivity, you landed on this page in a trice.

But how does it work? Have you ever thought about how that cat picture actually gets from a server in Oregon to your PC in London? We’re not simply talking about the wonders of TCP/IP, or pervasive Wi-Fi hotspots, though those are vitally important as well. No, we’re talking about the big infrastructure: the huge submarine cables, the vast landing sites and data centres with their massively redundant power systems, and the elephantine, labyrinthine last-mile networks that actually hook billions of us to the Internet.

And perhaps even more importantly, as our reliance on omnipresent connectivity continues to blossom, the number of our connected devices swells, and our thirst for bandwidth knows no bounds, how do we keep the Internet running? How do Verizon or Virgin reliably get 100 million bytes of data to your house every second, all day every day?

Well, we’re going to tell you over the next 7,000 words.

Table of Contents

    The secret world of cable landing sites
    Armoured submarine cables
    Fixing cables at sea
    QAM, DWDM, QPSK...
    The cable guise
    Testing submarine cables
    The power of nightmares
    Next stop: Data centre
    A change in the data tide
    The NOC's NOC
    The ISP's ISP's SLA
    The last mile
    VDSL2
    DOCSIS
    The last 100 metres
    Back to the future of wired Internet
    Quite a trip


[…]

Continua qui: http://arstechnica.co.uk/information-technology/2016/05/how-the-internet-works-submarine-cables-data-centres-last-mile/