ip prefix-list rfc1918-dsua - "Documenting Special Use

Hello,

I've been revisiting this topic which has been brought up many times
in one form or another on this list. Today I stumbled upon a
reference to a Cisco document with this prefix list.

It is a general purpose prefix list meant for external BGP peerings.
I understand that this prefix lists includes the RFC1918 range and
other special purpose address ranges but not full RFC 3330. I take it
to mean that this list is "good practice".

ip prefix-list rfc1918-dsua deny 0.0.0.0/8 le 32
ip prefix-list rfc1918-dsua deny 10.0.0.0/8 le 32
ip prefix-list rfc1918-dsua deny 127.0.0.0/8 le 32
ip prefix-list rfc1918-dsua deny 169.254.0.0/16 le 32
ip prefix-list rfc1918-dsua deny 172.16.0.0/12 le 32
ip prefix-list rfc1918-dsua deny 192.0.2.0/24 le 32
ip prefix-list rfc1918-dsua deny 192.168.0.0/16 le 32
ip prefix-list rfc1918-dsua deny 224.0.0.0/4 le 32
ip prefix-list rfc1918-dsua permit 0.0.0.0/0 le 32

Should it include the Class E deny 240.0.0.0/4 possibly? Otherwise
does it look accurate and make sense to memorize (versus a longer list
such as RFC3330)?

-Rich

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Received on Thu May 21 2009 - 13:54:52 ART