Service Tag
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... NAPTR resource
records for example.com, shown in the figure below, where "WP" is the
imagined application service tag for "white pages" and "EM" is the
application service tag ...
... application service tag for "white pages" and "EM" is the
application service tag for an imagined "Extensible Messaging"
application service.
...
... IANA-registered service; see Section 7
for instructions on registering new application service tags.
...
...
This document calls for two IANA registries: one for application
service tags, and one for application protocol tags.
...
... Application Service Tag IANA Registry ...
... registry for S-NAPTR
Application Service Tags, listing at least the following information
for each such tag:
...
... service defined in section 6.5.
o Defining publication: The RFC used to define the Application
Service Tag, as defined in the registration process, below.
...
... registration process, below.
An initial Application Service Tag registration is contained in [9].
...
...
o application protocol or service tag,
o intended usage,
...