The Mathematical Reality of IP Addressin in IPv4...

Alex P. Rudnev alex at
Fri Aug 27 10:05:45 UTC 1999

>  10010000 00000001 00000000 00000000
> Or, in other words everyhting starting with 144.1 as the first two octets
> is on the same network.
> What this proposal appears to be proposing is to permit NON-CONTIGUOUS
> netmasks such as:
It was obvious, through the author did a lot to mascarade this simple 
idea amongs the heap of words -:).

Just as the resume - it's not problem to use broadcast bits, it's not 
a problem to propose non-contiguous network masks, but (1) hosts do not 
know masks at all, IP address only, and (2) 99% existing routing 
protocols and ip forwarding software can't work with non-contiguous masks 
at all.

But I think it is nessesary to establish some aware for the such works - 
when so plain idea is described by so complex way -:). 

> In all reality, I think that the IP address problem is solving itself.
> The majority of the customers I deal with have a SINGLE ip address for all
> of their internal machines.  I have actually allocated LESS space than I
> have reclaimed over the past year and a half from customers who have moved
> to Private Address space.   To facilitate this I sell them a $250 "iGate
No doubt. Using private address space + NAT decrease the address needs 
and (important) increase your security a lot (except, of course, L4/L7 
viruses, trojans, etc... - usial student's mistake is to forgot about 
this levels).

> Junior" which is basically a 486 with some software I've put together in
> house (shameless plug).   The iGate Jr. basically takes all of the inside
> requests and NAT's them into a single outside address.  It also takes
> inbound connections for Mail and other services and routes them to the
> appropriate inside box.   As a result, a typical small-to-medium sized
> company only needs ONE real ip address in most circumstances. 
JUst as I'v wrote yesterday - if you allow to assign WWW addresses (or 
exactly, SERVICE addresses) to the _IP:PORT_ instead of _IP_ (and ask 
_give the port from your local _service_ table_, you'll be free in usage 
the same IP address even for the incoming services, not for the clients 
only (as todays).

> - Forrest W. Christian (forrestc at KD7EHZ
> ----------------------------------------------------------------------
> iMach, Ltd., P.O. Box 5749, Helena, MT 59604
> Solutions for your high-tech problems.                  (406)-442-6648
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Aleksei Roudnev, Network Operations Center, Relcom, Moscow
(+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41, N 13729 (pager)
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