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

service name


Click on the red underlined text to get to the source

... 4]) Application to map domain name, application service name, and application protocol dynamically to target ...


... That is, although SRV records can be used to map from a specific service name and protocol for a specific domain to a specific server, SRV records ...



Google
Web
RFC-Ref