North American Network Operators Group
Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: Security gain from NAT

  • From: Valdis . Kletnieks
  • Date: Tue Jun 05 21:49:04 2007 
On Tue, 05 Jun 2007 17:44:40 PDT, Roger Marquis said:
> 
> >> Sure, very easily, by using NAT between the subnets.
> >
> > Have at it. Nothing like trying to reach 10.10.10.10 nad having
> > to put in a dns entry pointing to 172.29.10.10
> 
> End-users prefer hostnames to IPs.  DNS hostnames are valid on both
> sides due to either local zone files or a DNS protocol-NAT.  It's a
> no-brainer to implement and a lot easier than using public address
> space given the relatively complex firewalling and filtering that
> requires.

So now the cruft extends and embraces, and you have to play DNS view games
based on whether it's on company A's legacy net, company B's legacy net,
or the DMZ in between them, and start poking around in the middle of DNS
packets to tweak the replies (which sort of guarantees you can't deploy DNSSEC).

And if the company aquires *another* one with rfc1918 on their legacy net,
then you get to play "as seen from A, B, or C, or this DMZ, or that DMZ"..

I think somebody on this list mentioned that due to corporate acquisitions,
there were legitimate paths between machines that traversed 5 or 6 NATs.

But yeah, "Sure, very easily".  Whatever you say...

Attachment: pgp00012.pgp
Description: PGP signature