[54052] in North American Network Operators' Group
/8s and filtering
daemon@ATHENA.MIT.EDU (Harsha Narayan)
Tue Dec 10 04:23:51 2002
Date: Tue, 10 Dec 2002 01:23:17 -0800 (PST)
From: Harsha Narayan <hnarayan@cs.ucsd.edu>
To: <nanog@merit.edu>
Errors-To: owner-nanog-outgoing@merit.edu
Hello,
Currently APNIC's policy means that if an organization can fully use a
/26 (since 25% of /24=/26 and to satisfy the multihoming requirement the
organization will need to have a prefix advertised by two or more ISPs) it
can get a multihoming assignment from APNIC.
If Class C /8s are over and ISPs maintain their filtering policies, the
bar would be raised to fully using a /24 instead (since 25% of /22 =
/24 and filtering in Class A is done at /22).
8 of the 9 APNIC /8s are from the Class C space. Only one is from the
Class A space. However there are only three untouched /8s left in the
Class C space - 197/8, 222/8, 223/8.
Actually, I wanted to know if the filtering policies will change to
accommodate this - i.e. will /24s be allowed in the Class A space?
I was also curious about this - if I am a customer who wants to
multihome and can justify only a /24, I would go to an ISP
which has an allocation from the Class C space rather than one from the
Class A space. Do ISPs get to choose where the allocation comes from?
Harsha.
