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Thursday, September 20, 2012

Reading List: Tubes

Blum, Andrew. Tubes. New York: HarperCollins, 2012. ISBN 978-0-06-199493-7.
The Internet has become a routine fixture in the lives of billions of people, the vast majority of whom have hardly any idea how it works or what physical infrastructure allows them to access and share information almost instantaneously around the globe, abolishing, in a sense, the very concept of distance. And yet the Internet exists—if it didn't, you wouldn't be able to read this. So, if it exists, where is it, and what is it made of?

In this book, the author embarks upon a quest to trace the Internet from that tangle of cables connected to the router behind his couch to the hardware which enables it to communicate with its peers worldwide. The metaphor of the Internet as a cloud—simultaneously everywhere and nowhere—has become commonplace, and yet as the author begins to dig into the details, he discovers the physical Internet is nothing like a cloud: it is remarkably centralised (a large Internet exchange or “peering location” will tend grow ever larger, since networks want to connect to a place where the greatest number of other networks connect), often grungy (when pulling fibre optic cables through century-old conduits beneath the streets of Manhattan, one's mind turns more to rats than clouds), and anything but decoupled from the details of geography (undersea cables must choose a route which minimises risk of breakage due to earthquakes and damage from ship anchors in shallow water, while taking the shortest route and connecting to the backbone at a location which will provide the lowest possible latency).

The author discovers that while much of the Internet's infrastructure is invisible to the layman, it is populated, for the most part, with people and organisations open and willing to show it off to visitors. As an amateur anthropologist, he surmises that to succeed in internetworking, those involved must necessarily be skilled in networking with one another. A visit to a NANOG gathering introduces him to this subculture and the retail politics of peering.

Finally, when non-technical people speak of “the Internet”, it isn't just the interconnectivity they're thinking of but also the data storage and computing resources accessible via the network. These also have a physical realisation in the form of huge data centres, sited based upon the availability of inexpensive electricity and cooling (a large data centre such as those operated by Google and Facebook may consume on the order of 50 megawatts of electricity and dissipate that amount of heat). While networking people tend to be gregarious bridge-builders, data centre managers view themselves as defenders of a fortress and closely guard the details of their operations from outside scrutiny. When Google was negotiating to acquire the site for their data centre in The Dalles, Oregon, they operated through an opaque front company called “Design LLC”, and required all parties to sign nondisclosure agreements. To this day, if you visit the facility, there's nothing to indicate it belongs to Google; on the second ring of perimeter fencing, there's a sign, in Gothic script, that says “voldemort industries”—don't be evil! (p. 242) (On p. 248 it is claimed that the data centre site is deliberately obscured in Google Maps. Maybe it once was, but as of this writing it is not. From above, apart from the impressive power substation, it looks no more exciting than a supermarket chain's warehouse hub.) The author finally arranges to cross the perimeter, get his retina scanned, and be taken on a walking tour around the buildings from the outside. To cap the visit, he is allowed inside to visit—the lunchroom. The food was excellent. He later visits Facebook's under-construction data centre in the area and encounters an entirely different culture, so perhaps not all data centres are Morlock territory.

The author comes across as a quintessential liberal arts major (which he was) who is alternately amused by the curious people he encounters who understand and work with actual things as opposed to words, and enthralled by the wonder of it all: transcending space and time, everywhere and nowhere, “free” services supported by tens of billions of dollars of power-gobbling, heat-belching infrastructure—oh, wow! He is also a New York collectivist whose knee-jerk reaction is “public, good; private, bad” (notwithstanding that the build-out of the Internet has been almost exclusively a private sector endeavour). He waxes poetic about the city-sponsored (paid for by grants funded by federal and state taxpayers plus loans) fibre network that The Dalles installed which, he claims, lured Google to site its data centre there. The slightest acquaintance with economics or, for that matter, arithmetic, demonstrates the absurdity of this. If you're looking for a site for a multi-billion dollar data centre, what matters is the cost of electricity and the climate (which determines cooling expenses). Compared to the price tag for the equipment inside the buildings, the cost of running a few (or a few dozen) kilometres of fibre is lost in the round-off. In fact, we know, from p. 235 that the 27 kilometre city fibre run cost US$1.8 million, while Google's investment in the data centre is several billion dollars.

These quibbles aside, this is a fascinating look at the physical substrate of the Internet. Even software people well-acquainted with the intricacies of TCP/IP may have only the fuzziest comprehension of where a packet goes after it leaves their site, and how it gets to the ultimate destination. This book provides a tour, accessible to all readers, of where the Internet comes together, and how counterintuitive its physical realisation is compared to how we think of it logically.

In the Kindle edition, end-notes are bidirectionally linked to the text, but the index is just a list of page numbers. Since the Kindle edition does include real page numbers, you can type in the number from the index, but that's hardly as convenient as books where items in the index are directly linked to the text. Citations of Internet documents in the end notes are given as URLs, but not linked; the reader must copy and paste them into a browser's address bar in order to access the documents.

Posted at September 20, 2012 21:47