[dns-operations] What is the exact response?

[scottjiang1415 at hotmail.com]

Dear friends:
When the resolver sends the DNSKEY RR query, irrespecitve of keyrollover period, I think the response message should reply a KSK, a ZSK and a RRSIG(DNSKEY). However, when I capture the package with tcpdump, the response message is unanticipated. 
I get the response with one KSK， two ZSKs and one RRSIG（DNSKEY）while we send DNSKEY RR query to root.
For example, 
 
I get the response with one KSK， one ZSKs and one RRSIG（DNSKEY）while we send DNSKEY RR query to com zone.
For example,
 
I get the response with one KSK， one ZSKs and two RRSIG（DNSKEY）while we send DNSKEY RR query to comcast.com zone.
For example,
 .
So, my question is that what is the exact result of DNSKEY RR query, how I calculate their message size?





scottjiang1415 at hotmail.com
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