Uniform Resource Names (URN) 2014-11-24 2023-05-25 Specification Required Dale Worley service Specific telephony service used in this call service:normal Normal ring/ringback rendering (default value) service:call-waiting Call waiting was initiated at the other side of the call service:forward Call has been forwarded service:recall:callback Recall due to callback service:recall:hold Recall due to call hold service:recall:transfer Recall due to transfer source Classification of the other party to the call source:unclassified Unclassified ring/ringback rendering (default value) source:internal User at the other side of the call is internal to the enterprise or PBX system source:external User at the other side of the call is external to the enterprise or PBX system source:friend User at the other side of the call is a friend source:family User at the other side of the call is a family member priority Priority of the call priority:normal Normal ring/ringback rendering (default value) priority:low Low priority call priority:high High priority call duration Duration of alerting signal duration:normal Normal ring/ringback rendering (default value) duration:short Shorter than normal duration:long Longer than normal delay Delay of rendering of alerting signal delay:none Immediate alerting (default value) delay:yes Delayed alerting locale Location-specific alerting signals locale:default Alerting not location-specific (default value) locale:country:<ISO 3166-1 country code> Alerting according to the conventions of the specified country service:crs Customized Ringing Signal (CRS) 3GPP TS 24.183 First Come First Served example IETF mailto:rai-ads&tools.ietf.org Lionel Morand mailto:lionel.morand&orange.com 2023-05-12