Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 25 Sep 2000 07:29:38 +0200
From:      sthaug@nethelp.no
To:        tom@sdf.com
Cc:        abcjr@southwind.net, freebsd-isp@FreeBSD.ORG
Subject:   RE: Using 'private net' IPs for WAN Addresses
Message-ID:  <98411.969859778@verdi.nethelp.no>
In-Reply-To: Your message of "Sun, 24 Sep 2000 21:19:54 -0700 (PDT)"
References:  <Pine.BSF.4.05.10009242113050.3189-100000@misery.sdf.com>

next in thread | previous in thread | raw e-mail | index | archive | help
> > Here is a great description on why one should not use RFC 1918 addresses
> > for inter-router links:
> > 
> > http://www.worldgate.com/~marcs/mtu/
> 
>   Wow... MTU path detection.  Most routers use the same MTU on all
> interfaces, so it isn't a factor.

Sorry, that's wrong. There are plenty of routers with 1500 byte Ethernet
MTUs, and considerably higher MTUs on serial/ATM/SDH interfaces.

>   Next, if you assign a /30 for every p2p interface, you can only achieve
> 50% utilization of the address space (2 used out of 4).  That isn't enough
> to meet the threshold to get more address space.  I know a a network
> provider that is numbering hundreds of p2p links just to free up address
> space because they don't meet the density requirements.

So you have only 50% utilization of the address space for your p-p links.
Unless you are very different from other providers, this is going to be a
very small fraction of your total address space.

Not using RFC 1918 addresses for p-p links on the Internet is still good
advice.

Steinar Haug, Nethelp consulting, sthaug@nethelp.no


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-isp" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?98411.969859778>