RFC 3958:Domain-Based Application Service Location...
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RRset


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... { NAPTR-RRset = [DNSlookup of NAPTR RRs for target ...
... target] [sort NAPTR-RRset by ORDER,and PREF within each ORDER] rr-done = false cur-rr = [first NAPTR ...
... { SRV-RRset = [DNSlookup of SRV RRs for target ...
... target] [sort SRV-RRset based on PREF] target = [target ...
... target of first RR of SRV-RRset] port = [port ...
... port in first RR of SRV-RRset] } ...
... application-specific protocol with the DNS lookup and RRset processing described in the pseudocode and continue the S- NAPTR ...



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