RE: [NTISP] Did I not learn something. Why does this work

David V. Brenner ( (no email) )
Tue, 1 Dec 1998 20:48:26 -0800

It works because it is actually the long form ("dotless") of the IP address.
This is merely another method of expressing the very large number that makes
up an IP address. It is similar to the way we shorten 8-bit binary numbers
to two-character hexadecimal notation, only we're doing it with decimal
instead of binary. In this case, the four-octet expression we use is dealt
with just like any other number system, where each placeholder in the number
is multiplied by an exponent of the system base. In decimal, we see 1, 10,
100, 1000, etc. In this system, it's 1, 256, 256^2, 256^3. So, an IP
address of a.b.c.d works out to be:

(a * (256^3)) + (b * (256^2)) + (c * 256) + (d*1)

It's rather clever, actually. A neat geek parlor trick.

It was also a recent security concern when someone discovered that the
absence of dots caused Internet Explorer to misinterpret such addresses as
intranet addresses, which then opened the browser to other exploits. Cool,
eh? :/

David V. Brenner -
International Services Network Corporation

> -----Original Message-----
> From:
> []On Behalf Of greg Lowthian
> Sent: Tuesday, December 01, 1998 7:50 PM
> To:
> Subject: [NTISP] Did I not learn something. Why does this work
> http://031652470396/
> ________ This E-mail Message is From:
> |\______/| Greg Lowthian
> |________| Isat Network
> ICQ: 198610 (work)
> ICQ: 14331858 (home)
> For more information about this list, including removal,
> see this url: