[CentOS] how is this possible?

Thu Jun 21 03:37:55 UTC 2012
Woodchuck <marmot at pennswoods.net>

On Wed, Jun 20, 2012 at 11:21:41PM -0400, Bob Hoffman wrote:
> I got a spam today (from a yahoo server, surprise!) with nothing but a 
> single link.
> http://     2927755261/
> I separated the http so it would not be a link in your email... suggest 
> not going to it without proper measures.
> it takes you to a record search site.
> When I look up this number block here,
> http://www.ip-adress.com/ip_tracer/2927755261
> it comes up with a different ip address...
> The ip address has no correlation to the numbers I searched for though.

Oh, yes it does.  is the same IPA.  It's the same number in the
same way that 0x0f and 15 are the same number.

> How is it possible to have a url that does not conform to the internet 
> standards?

It does conform.

> Even ip addresses need 'periods' between each group of numbers....

No, they don't.  That's the trick.  There are no groups of numbers
in an IPA, they exist only in our minds.

2927755261 here is  just a decimal number.  The "dotted quad" is a
way to specify each byte of a 32 bit IPA, akin to using hex numbers.
This is the decimal number it corresponds to. (and it's the way
software stores IPAs internally, just another integer.)  There are
byte-order issues, see man htonl(3) and man ntohl(3).