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Mythbusters #2: Stanford has more IP addresses than China

  • Artikkeli

Let's tackle our second myth.  There is a factoid on the Internet that some American universities (normally listed as either Stanford or MIT) have more IP addresses than the entire country of China.  This has been repeated in the mainstream press so often (To the edge of cyberspace, United Nations ponders Net's future, etc), it has to be true, right?

If we take a look at the statistics located at http://ftp.apnic.net/stats/apnic/assigned-apnic-latest (Warning: non-user friendly; heavy befuddlement factor; do not operate heavy machinery while deciphering) we will find that China currently has nine IPv4 /8 address blocks assigned to it.  I'm sure you can all do CIDR notation off the top of your head, but for those who can't, a single /8 address block contains about 16,777,216 addresses.  Since China has about nine of these, it means that they have roughly 151 million (9*16,777,216) IP addresses.

Looking at http://ws.arin.net/whois/, we can see that Stanford has been assigned five/16s, each of which contains about 65,536 addresses.  Multiplying this out (5*65,536) gives us about 327,680 total addresses.  (There are some additional suballocations assigned, but they are all pretty small, and all appear to add up to less than 500 addresses, so for simplicity sake, I am ignoring them)

Now, I was not a math major, but even I can figure out that 151 million is a LOT bigger than 327,680.

Also, if we look at http://ws.arin.net/whois we can see that MIT still has their /8 allocation along with several /24 blocks and a couple of /16 blocks, but even all of these added together still fall well short of nine /8s that China possesses.  

The moral to this story is that China has a LOT of IP addresses - far more than Stanford and MIT combined! This myth is definitely BUSTED.

But before we move on, how did this myth come to life? Why would anyone say this?

This is a factoid that became untrue with age. It was true when the Internet was in its infancy, around 1995-1998. At that point, Stanford was assigned a Class A address (what we call a /8 using CIDR notation) which gave them about 16 million addresses, while China only had a few Class Bs (/16s).  That all changed around 2000, though, when (a) Stanford turned their /8 address block back in, and (b) China began requesting more addresses. At that point (2000-2001) China received the equivalent of a /8 address and has been increasing their web presence ever since.  Today, China is one of the fastest growing sectors of the APNIC (the organization that assigns IP addresses in the Asia-Pacific region)

For more information see:

APNIC - IP Addressing in China

IP Addressing Changes at Stanford

Comments

  • Anonymous
    January 01, 2003
    Technically they could have 2,148,270,080 working addresses if they're using PAT. So yes they'd have more in one occassion. Same for China, 916,777,21665536 ... Want to further divide... Segment those PAT's into routers and re-PAT http://en.wikipedia.org/wiki/Port_address_translation