Collecting DTMF digits (continued 2)

Collecting DTMF digits (continued)

Controller issues a “re-Invite” at 11 which looks like:

INVITE sip:UserB@there.com SIP/2.0
Via: SIP/2.0/UDP 100.101.102.103
To: UserB <sip:UserB@there.com
From: User A sip:UserA@here.com
Call-ID: a84b4c76e66710100.101.102.103
CSeq: 1 INVITE
Contact: sip:UserB@there.com
Content-Type: application/sdp
Content-Length:
…
v=0 o=UserA 289375749 289375749 IN IP5 100.101.102.103
S=- c=IN IP4 100.101.102.103
t=0 0
m=audio 5004 RTP/AVP 0
m=audio 53000 RTP/AVP 0
c=IN IP4 200.201.202.203
a=rtpmap:96 telephone-event

Note the 2nd “m=audio” line in the SDP (see Sinnreich Johnston page 257), this second connection is the RTP connection to the DTMF digit collector.


Transcript

[slide489] The collected digits get collected and returned.