[RPZ] Compression

Fred Morris m3047 at m3047.net
Wed Apr 13 21:12:30 UTC 2011

Meant to post this to the list, but I see that I did not...

On Saturday 09 April 2011 19:14, Fred Morris wrote:
> While LHS compression is well-understood, it's not clear to me (just quickly 
> scanned 1035 again) what compression is applied to the RHS in an RR... [...]

Re-rereading.. yes there is compression on the RHS when the RDATA is defined 
to be a domain name:

"Pointers can only be used for occurances of a domain name where the
format is not class specific.  If this were not the case, a name server
or resolver would be required to know the format of all RRs it handled." (RFC 
1035, secton 4.1.4

So that does include CNAMEs.

(Thanks, Paul! I looked at a packet dump just to convince myself.)


Fred Morris

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