filter language # filter out prefixes longer than 24 or shorter than 8 bits deny from any allow from any prefixlen 8 - 24 # do not accept a default route deny from any prefix 0.0.0.0/0 # filter bogus networks deny from any prefix 10.0.0.0/8 prefixlen >= 8 deny from any prefix 172.16.0.0/12 prefixlen >= 12 deny from any prefix { 192.168.0.0/16 169.254.0.0/16 } prefixlen >= 16 deny from any prefix 192.0.2.0/24 prefixlen >= 24 deny from any prefix { 224.0.0.0/4 240.0.0.0/4 } prefixlen >= 4