RFC 3263:Session Initiation Protocol (SIP): Locati...
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domain name


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... protocol fields, (if the server is using a site certificate), the domain name in the query and the domain name ...
... certificate), the domain name in the query and the domain name in the replacement field MUST both be valid based on the site ...
... by the server in the TLS exchange. Similarly, the domain name in the SRV query and the domain name ...
... domain name in the SRV query and the domain name in the target in the SRV record ...
... client performs an A or AAAA record lookup of the domain name. The result will be a list of IP addresses, each of which can be contacted at the specific port ...
... AAAA record lookup of the domain name. The result will be a list of IP addresses, each of which can be contacted using the transport protocol determined previously, at the default port ...


... TCP to send the response. If, however, the sent-by field contained a domain name and a port number, the server queries for A or AAAA records ...
... before it results in a failure. If, however, the sent-by field contained a domain name and no port, the server queries ...
... the server queries for SRV records at that domain name using the service identifier ...


... SRV provides a way to fix this. Instead of using an IP address, a domain name that resolves to an SRV record can be used: ...



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