keith has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-msc/+/28509 )
Change subject: Change CC_CAUSE returned on unanswered MT Call ......................................................................
Change CC_CAUSE returned on unanswered MT Call
The timer "mgw X2" (RTP stream establishing timeout) is set by default to 30 seconds. When an MT call is ringing and remains unanswered, it is this timer that will expire, and the call is terminated.
Up to now this results in a CC_CAUSE of Resource Unavailable and if osmo-sip-connector is in use, the SIP agent will get 503 Service Unavailable. While "resource unavailable" may be technically correct, in that the MGW did not return an rtp stream in time, returning "No User Responding" (resulting in SIP 480) is probably a more accurate description of what actually happened, allowing the switch to inform the caller.
Change-Id: I4a9cfc388ec9ecb743d154a114a6db638eac4701 --- M src/libmsc/gsm_04_08_cc.c 1 file changed, 2 insertions(+), 0 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-msc refs/changes/09/28509/1
diff --git a/src/libmsc/gsm_04_08_cc.c b/src/libmsc/gsm_04_08_cc.c index 6562daa..9b7495f 100644 --- a/src/libmsc/gsm_04_08_cc.c +++ b/src/libmsc/gsm_04_08_cc.c @@ -278,6 +278,8 @@ if (trans->cc.mncc_initiated) { mncc_release_ind(trans->net, trans, trans->callref, GSM48_CAUSE_LOC_PRN_S_LU, + (trans->cc.state == GSM_CSTATE_CALL_RECEIVED) ? + GSM48_CC_CAUSE_USER_NOTRESPOND : GSM48_CC_CAUSE_RESOURCE_UNAVAIL); }