# Asterisk Project : chan_sip Channel Variables

Added by mdavenport , edited by mdavenport on Aug 31, 2010

- ${SIPCALLID} * - SIP Call-ID: header verbatim (for logging or CDR matching)
- ${SIPDOMAIN} * - SIP destination domain of an inbound call (if appropriate)
- ${SIPFROMDOMAIN} - Set SIP domain on outbound calls
- ${SIPUSERAGENT} * - SIP user agent (deprecated)
- ${SIPURI} * - SIP uri
- ${SIP_MAX_FORWARDS} - Set the value of the Max-Forwards header for outbound call
- ${SIP_CODEC} - Set the SIP codec for an inbound call
- ${SIP_CODEC_INBOUND} - Set the SIP codec for an inbound call
- ${SIP_CODEC_OUTBOUND} - Set the SIP codec for an outbound call
- ${SIP_URI_OPTIONS} * - additional options to add to the URI for an outgoing call
- ${RTPAUDIOQOS} - RTCP QoS report for the audio of this call
- ${RTPVIDEOQOS} - RTCP QoS report for the video of this call