4 Dec
2020
4 Dec
'20
1:38 a.m.
On 03/12/2020 13.39, Andrew Chen wrote:
Hi all,
I was wondering if someone can help me understand how the ICE
parameter works in the rtpengine module works.
So basically our client does an ICE candidate lookup and grabs a list
of them and applies it to the INVITE that gets sent to the Kamailio.
The list looks like this:
2020-12-03T18:05:46.456030+00:00 ashmainkama51 kamailio[22147]:
a=candidate:3373280875 1 udp 2122262783
2001:8a0:78fc:7000:e1d7:e93:3c50:ee71 59827 typ host generation 0
network-id 2 network-cost 10
2020-12-03T18:05:46.456057+00:00 ashmainkama51 kamailio[22147]:
a=candidate:3040609428 1 udp 2122197247
2001:8a0:78fc:7000:d979:bf75:dbc0:69f 59828 typ host generation 0
network-id 3 network-cost 10
2020-12-03T18:05:46.456081+00:00 ashmainkama51 kamailio[22147]:
a=candidate:1681997092 1 udp 2122129151 192.168.1.66 59829 typ host
generation 0 network-id 1 network-cost 10
2020-12-03T18:05:46.456106+00:00 ashmainkama51 kamailio[22147]:
a=candidate:2274611867 1 tcp 1518283007
2001:8a0:78fc:7000:e1d7:e93:3c50:ee71 9 typ host tcptype active
generation 0 network-id 2 network-cost 10
2020-12-03T18:05:46.456131+00:00 ashmainkama51 kamailio[22147]:
a=candidate:4223662180 1 tcp 1518217471
2001:8a0:78fc:7000:d979:bf75:dbc0:69f 9 typ host tcptype active
generation 0 network-id 3 network-cost 10
2020-12-03T18:05:46.456155+00:00 ashmainkama51 kamailio[22147]:
a=candidate:717406676 1 tcp 1518149375 192.168.1.66 9 typ host tcptype
active generation 0 network-id 1 network-cost 10
2020-12-03T18:05:46.456180+00:00 ashmainkama51 kamailio[22147]:
a=candidate:2130547417 1 udp 8199935 206.81.191.27 61165 typ relay
raddr 85.247.0.121 rport 53091 generation 0 network-id 1 network-cost 10
In the rtpengine_offer, I have this:
rtpengine_offer("ICE=force DTLS=passive replace-session-connection
replace-origin external internal");
What i am trying to do is to tell the freeswitch endpoint to use
rtpengine as ICE candidate and I see in the SDP this is happening:
a=candidate:6296910676 1 udp 659136 206.81.191.52 52766 typ host
generation 0
Btw..206.81.191.52 is a separate AWS instance running rtpengine binary.
On the rtpengine_answer, I tell the remote client side the same
thing..use rtpengine as your ICE candidate:
rtpengine_answer("ICE=force DTLS=passive replace-session-connection
replace-origin internal external");
and this is snippet from 200 OK:
a=candidate:6296910676 1 udp 659136 206.81.191.52 52766 typ host
generation 0
Question:
Why does the rtpengine logs still show that it's trying to use
2001:8a0:78fc:7000:e1d7:e93:3c50:ee71 as RTP candidate in this scenario?
Dec 3 18:05:47 ashmainrtpe42 rtpengine[8505]: DEBUG:
[ep1sbnkk9tikhg4kpmot]: Forward to sink endpoint:
2001:8a0:78fc:7000:e1d7:e93:3c50:ee71:59827 (RTP seq 25423 TS 0)
I thought ICE=force will handle such adjustments so that all rtp is
handled by the rtpengine to our client and bypass the STUN server?
Isn't that what's happening? Rtpengine receives media from one peer and
forwards it to one of the ICE candidates (presumably the primary one
that was negotiated) of the other peer. Or am I misunderstanding what
you posted?
Cheers