The twilight of /8s

A “/8” is a block of 16,777,214 usable IP addresses. That’s a big fraction of the entire IPv4 address space – about 1/224, in fact. Each one is all the addresses that begin with a given number: 10.0.0.0/8 is all the IP addresses that begin with “10.”, “184.0.0.0/8” (or “184/8” for short) is all the IP addresses that begin with “184.” and so on.
How are they used? You can see in this map of the entire IPv4 Internet as of 2006.
For the IPv6 map just imagine the XP default desktop picture.
In the early days of the Internet /8s were given out directly to large organizations. If you look near the middle-top of the map, just left of “MULTICAST” and above “DISA” you can see “MIT”.
The Massachusetts Institute of Technology got into the Internet game pretty early. This is the first map I have where they appear, in June 1970:

The Laboratory for Computer Science at MIT were assigned the 18.0.0.0/8 block sometime around 1977, according to RFC 739, though it looks like they may have been using it since at least 1976.
By 1983 (RFC 820) it belonged to the whole of MIT, rather just the CS Lab, though you have to wonder how long term that was supposed to be, given the block was named “MIT-TEMP” by 1983 (RFC 870). According to @fanf (who you should follow) it was still described as temporary until at least the 1990s.
But no longer. MIT is upgrading much of their network to IPv6, and they’ve found that fourteen million of their sixteen million addresses haven’t been used, so they’re consolidating their use and selling off eight million of them, half of their /8. Thanks, MIT.
Who else is still sitting on /8s? The military, mostly US, have 13. US Tech companies have 5. Telcos have 4. Ford and Daimler have one each. The US Post Office, Prudential Securities, and Societe Internationale de Telecommunications Aeronautiques each have one too.
One is set aside for use by amateur radio.
And two belong to you.
10.0.0.0/8 is set aside by RFC 1918 for private use, so you can use it – along with 192.168.0.0/16 and 172.160.0.0/12 – on your home network or behind your corporate NAT.
And the whole of 127.0.0.0/8 is set aside for the local address of your computer. You might use 127.0.0.1 most of the time for that, but there are 16,777,213 other addresses you could use instead if you want some variety. Go on, treat yourself, they’re all assigned to you.

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Blackboxes and unknown effects

In my previous career I studied the effect of alcohol on developing embryos. It’s a bit weird I ended up in that field because embryological development always seemed to complex to me. And it was and is complicated. In a lot of ways, though, it was good training for deliverability. We dealt with a lot of processes that seem, on the surface, straightforward.
Fertilization happens, then you get a flat group of cells, those cells fold up into the neural tube, cells migrate around, things happen, limbs form, organs form and 21 days later you have a fluffy little chick.
The details in all those steps, though. They’re a bit more complicated, looking something like this:
There are lots of different things going on inside the embryo to take it from a single cell up to a complex multicellular being. Genes turn on, genes turn off at different times in development, often driven by overlapping concentration gradients. Genes turn each other and themselves on and off. It’s complex, though, and there are things that happen that we don’t quite understand and have to black box. “If I add this protein, or take this gene and that gene away… what happens?”
A lot of that is like what email reputation is these days. There isn’t one factor in reputation, there are hundreds or thousands. They interact with each other, sometimes turning up reputation, sometimes turning down reputation. We figure this out by poking at the black box and seeing what happens. Unlike development, though, delivery rules are not fixed. They are changing along the way.
It’s not simple to explain delivery and how all the moving parts interact with each other. We don’t always know that doing A will lead to X. Because A -> X is not a straight line and there are other things that impact that line. Those other things also impact A, X and each other.
Delivery is a tangled web. On the surface it seems simple, but when you start peeling back the layers you discover the jumble of factors that all interact with each other. It’s what makes this a challenging field for all of us.

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SHOUTY CAPS!!!

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Over at Meh Glenn Fleishman has put together a fascinating two-parter on the history of using ALL CAPS for emphasis. And SHOUTING.

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Who didn't invent email?

Who didn’t invent email? Shiva Ayyadurai.
He’s not the only one – I didn’t invent email either, nor did Abraham Lincoln, Boadicea or Tim Berners-Lee. So why mention Shiva?
He claims that in 1978 when he was 14, he took some courses in programming. His mum worked for the University of Medicine and Dentistry of New Jersey, and one of her colleagues challenged him to write an electronic mail system. And he did just that, creating a basic messaging system in FORTRAN, based on the existing paper memo format, ending up with a non-networked electronic mail system with similar functionality to mainstream applications that were in use well over a decade earlier.
That’s pretty impressive, and is the sort of thing that’ll look good on a college application form. (When I was 13 I designed and implemented a chassis dynamometer management unit that Shell’s research division used to test fuel and lube oil performance over virtual driving tracks – dozens of pages of 6502 assembly code, and you can be sure I put that on my college application form).
Some years later, in 1982, Shiva applied for and was granted a certificate of copyright registration on that piece of software. A copyright is not a patent – it recognizes and protects the expression of the work, not the idea underlying the work. There’s no real bar for copyright, other than it being a piece of work you created yourself – I automatically own copyright to anything I create, including software I’ve written and this blog post. Registering a copyright on a work, whether it be software or anything else, is a trivial exercise in bureaucracy – you fill in a form, you pay a registration fee, it gets rubber stamped. What is protected by the copyright is the work – in this case the software source code – itself, not the ideas, not the name of the package, nothing else. (I have copyright on my software package, Abacus. That doesn’t mean that I invented the Abacus.)
Meanwhile, Shiva moved into email marketing, founded a small ESP, and seems to be doing quite nicely (although a journalist who looked can’t find much evidence of the ESP being successful, or even existing, other than a lawsuit it filed against IBM and American Express for misappropriation of trade secrets in 2005).
Back in 2011, though, things started to get weird. Shiva started to use this copyright filing, and the fact that he used the title “EMAIL” on the filing, to support a claim that he was “the inventor of email”. It’s a compelling human interest / tech story to journalists whose knowledge of email and internet history is vague, so it got quite a bit of coverage.
(Shiva makes an image of his copyright certificate available: http://www.vashiva.com/images/vashiva_patent3_enl.jpg. Note that the URL describes it as a “patent”, rather than a copyright filing.)
It was quickly debunked. It didn’t pass the sniff test. Technical blogs started asking how the Washington Post and other press had fallen for this. The Washington Post clarified that pretty much all the significant claims in the original article were untrue.
It didn’t go away, though. Two-and-a-half years later, there’s a series of articles in the Huffington Post, pitching the same story, this time with a few unpleasant twists in it’s approach. It’s got a glossy infographic, filled with provably false claims. It has the feel of a professional PR campaign, rather than an article written by a reporter. Sure enough, it’s written by Larry Weber, a high powered PR guy (CEO of RacepointGlobal – who “build the right influencer relationships for your brand” – and CEO of Weber Public Relations Worldwide). There are at least five article in the series, all written by different people, but having oddly similar phrasing.
Shiva’s ESP, EchoMail, and their current branding is based around his (false) claim to be the “Inventor of Email”, so there’s clearly money as well as ego at stake. Neither Larry Weber nor the Huffington Post mentioned that Larry Weber is also on the board of EchoMail.
So we’re going through the debunking process again. I was going to write more, but others are way ahead of me.
 

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