industry filtering rules

Wed Jun 3 19:06:12 UTC 1998

hi,

sprintlink's filter policy for non sprintlink customers is shown below.  
do other large providers have similar policies?  i am a sprintlink 
customer and am trying to understand how these policies are implemented 
in the industry.  thanks.

ip nums	cidr	

RFC 1918		Reserved Addresses Disallow 10.0.0.0/8, 172.16.0.0/12, and 
192.168.0.0/16
0-126 	/8	Allow no subnets of historical addresses that were not 
announced in July 1995
127-191 	/8	Allow nothing longer than /16 (i.e., /17, /18, /19, etc.)
192-205 	/8	Allow nothing longer than /24 (i.e., /25, /26, /27, etc.)
206-223 	/8	Allow nothing longer than /19 (i.e., /20, /21, /22, etc.)
195 	/8	Allow nothing longer than /19 (i.e., /20, /21, /22, etc.)
24	/8	Allow nothing longer than /19 (i.e., /20, /21, /22, etc.)

*The principal change is that we used to disallow /19s in 206/8-223/8 and 
195/8, and this was not; in line with the minimal allocation units 
performed by the three primary registries

Regards                                     

+++++++++++++++++++++++++++++++++++++++
+ Neil Lehrer                       
+ U.S. Information Agency         
+ Networks and Systems Support Division
+                                   
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+ fax      202 619-3883             
+ internet nlehrer at usia.gov         
+                                   
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