RFC 8768 PDF | Constrained Application Protocol (CoAP) Hop-Limit Option

Private Session Initiation Protocol (SIP) Extensions for Media Authorization

The W3C Speech Interface Framework Media Types: application/voicexml+xml, application/ssml+xml, application/srgs, application/srgs+xml, application/ccxml+xml, and application/pls+xml

Link-Layer Event Notifications for Detecting Network Attachments

Internet Key Exchange (IKEv2) Protocol