On Jan 6, 2011, at 10:08 AM, Joe Greco wrote:
Packing everything densely is an obvious problem with IPv4; we learned early on that having a 48-bit (32 address, 16 port) space to scan made port-scanning easy, attractive, productive, and commonplace.
I don't believe that host-/port-scanning is as serious a problem as you seem to think it is, nor do I think that trying to somehow prevent host from being host-/port-scanned has any material benefit in terms of security posture, that's our fundamental disagreement. If I've done what's necessary to secure my hosts/applications, host-/port-scanning isn't going to find anything to exploit (overly-aggressive scanning can be a DoS vector, but there are ways to ameliorate that, too). If I haven't done what's necessary to secure my hosts/applications, one way or another, they *will* end up being exploited - and the faux security-by-obscurity offered by sparse addressing won't matter a bit. This whole focus on sparse addressing is just another way to tout security-by-obscurity. We already know that security-by-obscurity is a fundamentally-flawed concept, so it doesn't make sense to try and keep rationalizing it in various domain-specific instantiations. ------------------------------------------------------------------------ Roland Dobbins <rdobbins@arbor.net> // <http://www.arbornetworks.com> Most software today is very much like an Egyptian pyramid, with millions of bricks piled on top of each other, with no structural integrity, but just done by brute force and thousands of slaves. -- Alan Kay