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- If the Flag field is blank, this indicates that the client must use the resulting domain name to look up other NAPTR records.
- The Service field specifies the service and protocol that are used to communicate with the NIOS-X Server at the domain name. In the example, the service field specifies that SIP (Session Initiation Protocol) is used to contact the telephone service.
- The regular expression specifies the substitution expression that is applied to the original string of the client. In the example, the regular expression !^.*$!sip:jdoe@corpxyzexample.com! specifies that the domain name 7.6.5.4.3.2.1.5.5.5.1.e164.arpa is replaced with sip:jdoe@corpxyzexample.com.
The regular expression in a NAPTR record is always applied to the original string of the client. It must not be applied to a domain name that resulted from a previous NAPTR rewrite. - The Replacement field specifies the FQDN for the next lookup, if it was not specified in the regular expression.
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