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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thirty.years.com

Thirty years ago this Sunday, symbolics.com was registered – the first .com domain. It was followed, within a few months, by bbn.com, think.com, mcc.com and dec.com.
Symbolics made lisp machines – symbolics.com is now owned by a domain speculator.
BBN is a technology R&D company who’ve worked on everything. If I had to pick one thing they were involved with it’d be the Internet Message Processor – the router used on the very first Internet nodes. They are still around, as a division of Raytheon.
Think.com made some amazing massively parallel computers. Their hardware group was bought out by Sun, who were bought out by Oracle and think.com now redirects to a broken error page at oracle.com.
Mcc.com were the first – and for a while, the largest – computing research and development consortium in the US. They did groundbreaking work on everything from silicon to AI. Their domain is now a generic parked page owned by a domain speculator.
Dec.com were Digital Equipment Corporation – creators of the PDP, VAX, Alpha and StrongARM processors, amongst many other things. They were a huge company when I worked for them designing Alpha CPUs in the mid 90s, then they were acquired by Compaq, then HP, then split up. Their domain is now a personal website.
It took nearly three years to reach 100 registered .com domains and nearly 10 years to reach 9,000.
As of this morning there are 116,621,517 domains registered in .com, from (64 zeros).com to (64 letter z).com, out of a possible total of more than two googol – so there’s still a domain there for you.
221,848 of those domains in .com mention “mail”.

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Truth, myths and realities

For a long time it was a known fact that certain ISPs recycled abandoned addresses into spamtraps. There were long discussions by senders about this process and how it happened. Then at a conference a few years ago representatives of ISPs got up and announced that they do not recycle addresses. This led to quite a bit of consternation about how deliverability folks were making things up and were untrustworthy and deceptive.

In the early 2000’s ISPs were throwing a lot of things at the wall to deal with mail streams that were 80 – 90% bulk. They tried many different things to try and tame volumes that were overwhelming infrastructure. ISPs did try recycled traps. I know, absolutely know, two did. I am very sure that others did, too, but don’t have specific memories of talking to specific people about it.
At that time, a lot of deliverability knowledge was shared through word of mouth. That turned into a bit of an oral history. The problem with oral history is that context and details get lost. We can use the story of the ISP that did/did not recycle traps as an example.
Deliverability folks talk about an ISP that recycles traps. They don’t mention how often it happens. Some folks make the assumption that this is an ongoing process. It’s not, but anyone who knows it’s not risks violating confidences if they correct it. Besides, if senders believe it’s an ongoing process maybe they’ll be better behaved. Eventually, the story becomes all ISPs recycle traps all the time. This is our “fact” that’s actually a myth.
Then an ISP employee goes to a conference an definitively states they don’t recycle traps. I believe he stated the truth as he knows it to be. That ISP moved on from recycled traps to other kinds of traps because there were better ways to monitor spam.
We were talking about this on one of the deliverability lists and I told another story.
[ISP] recycled addresses once – back when JD was there which must have been, oh, around 2005/6 or so. I heard this directly from JD. It wasn’t done again, but a whole bunch of people just assumed it was an ongoing thing. Since my knowledge was a private conversation between JD and me, I never felt comfortable sharing the information. Given the circumstances, I’ve decided it’s OK to start sharing that end of the story a little more freely.
No one set out to create a myth, it just happened. No one intended to mislead. But sometimes it happens.

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2016 Mary Litynski Award

The Mary Litynski Award is presented by M3AAWG to people who have done extensive work outside the public eye over a significant period of time. At the Dublin conference the award was presented to Rodney Joffe. A lot of other people will talk about Rodney’s accomplishments, including his role in the founding of Genuity, his work with the DMA in the early days of spam, his efforts against SMS spam and his efforts to secure the Internet infrastructure. But I have a much more personal perspective.
Rodney was seminal in changing my life and career path. Back in 1999, Rodney asked Steve to look into some DNS creativity he was testing. A few months later, Rodney invited Steve to join a new company he was founding based on that DNS creativity. We moved out the the Bay area and Steve started working for UltraDNS in early 2000.
Moving out to the Bay Area triggered my career shift into anti-spam and anti-abuse. I started working at MAPS (now Trend Micro) in their experimental consulting service division. We were the “carrot” end of the equation, where our job was to help companies minimize the abuse coming out of their networks.
After MAPS went through a round of layoffs in 2001, Rodney started recommending me as an email consultant to some of his connections in the marketing world. This work was a success and directly led to the founding of Word to the Wise and everything that flows from that.
M3AAWG has published a video where Rodney discusses his role in the history of spam and some of the other things he’s done to fight junk advertising (both fax and SMS spam). He sued junk faxers in small claims court. He was instrumental in getting SMS spam covered under the TCPA. He wrote the first global opt-out list supported by both the DMA and the ISPs and proved that global opt-out would never work. He literally pulled the plug on spamming customers.
Rodney says he’s “Not smart, just the guy who carries the bags of money and helps the smart people get things done.” I certainly don’t believe that is true. He has done things on the global scale to make the Internet a safer place for end users. But my appreciation is much more personal. I will forever be grateful to him for starting us on this path and the help and advice he gave us so many years ago.

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