[Asterisk-Users] IAX trunking frequency parameter works only on initiator side

[Branko Samardzic]

Hi,

I am experimenting with trunkfreq parameter.
When it is 20ms I can see both parties in IAX session sending IAX frames
every 20ms.
When I modify this parameter to 40ms then I can see that only server that
initiated
IAX connection works properly (i.e. sends IAX frames every 40ms while other
side still
sends IAX frames at 20ms per frame rate).
I disabled jitter buffers on both sides and I use speex codec.

Here is tcp dump of IAX traffic:

23:26:45.972072 IP SERVER_A.62142 > SERVER_B.4569: UDP, length 58
23:26:45.976295 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:45.996264 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.006742 IP SERVER_A.62142 > SERVER_B.4569: UDP, length 58
23:26:46.016270 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.036254 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.047891 IP SERVER_A.62142 > SERVER_B.4569: UDP, length 58
23:26:46.056248 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.076286 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.091255 IP SERVER_A.62142 > SERVER_B.4569: UDP, length 58
23:26:46.096262 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.116243 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25
23:26:46.127494 IP SERVER_A.62142 > SERVER_B.4569: UDP, length 58
23:26:46.136242 IP SERVER_B.4569 > SERVER_A.62142: UDP, length 25

SERVER_A initiates connection while SERVER_B answers.

SERVER_A iax.conf file
===================================================
[SERVER_B]

disallow=all
allow=speex

jitterbuffer=no
dropcount=2
maxjitterbuffer=200
maxexcessbuffer=100
minexcessbuffer=60
jittershrinkrate=1

trunkfreq=40                    ; How frequently to send trunk msgs (in ms)

context = foo
secret=zYX9VUt
auth=md5
type=friend
host=SERVER_B_IP_ADDRESS
trunk=yes


SERVER_B iax.conf file
===================================================
[SERVER_B]

disallow=all
allow=speex

jitterbuffer=no
dropcount=2
maxjitterbuffer=200
maxexcessbuffer=100
minexcessbuffer=60
jittershrinkrate=1

trunkfreq=40                    ; How frequently to send trunk msgs (in ms)

context = default
secret=zYX9V
auth=md5
type=friend
host=SERVER_B_IP_ADDRESS
trunk=yes


Any idea as to why trunking frequency is not symmetrical?
Any help is appreciated