[AusNOG] Bogon Filtering

[Mark Newton]

On Mon, Feb 13, 2012 at 04:22:45PM +1100, Chris Killian wrote:

 > Fairly open ended question but does filter these anymore. *Some companies
 > seem to think that as the IPV4 space has been fully allocated this is no
 > longer a requirement. However looking at the bogon lists there are still a
 > huge number of unallocted IPV4 address.
 > What do you guys think.

As someone who has had to spend weeks of his life on several 
occasions trying to convince networks utilizing bogon filtering to 
update themselves because APNIC had started allocating out of a 
new IANA /8 block, I can tell you that anyone who is still bogon
filtering is causing more harm than good, both to themselves and to
whatever passes for global internet connectivity these days.

What problem does bogon filtering solve?  Nothing that can't also
be solved with less effort by using firewalls, Ironports, and
other layer-5+ techniques.

There are no free /8 blocks left.  What exactly would you be filtering
anyway?

  - mark