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

service field


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... NAPTR record, the client examines the SERVICE field to find a match. In the case of the S-NAPTR DDDS application, this means a SERVICE field ...
... SERVICE field to find a match. In the case of the S-NAPTR DDDS application, this means a SERVICE field that includes the tags for the desired application service ...


... while (not rr-done) if ([SERVICE field of cur-rr contains desired application service and application protocol ...



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