[SR-Users] UDP-TCP bridging in-dialog SUBSCRIBE

[Dan Christian Bogos]

Hey Guys,

I have the following scenario:


UA1 (UDP) -> Kamailio Proxy -> (TCP) UA2

As per the signaling sample, I would expect that in-dialog SUBSCRIBEs 
are bridged between UDP and TCP network but for some reason this does 
not happen (the subscribe comes in over UDP and leaves still over UDP 
although tcp is present in the route headers). Are we somehow forced to 
mangle contact header and add transport parameter to it or the 
record-route headers should serve for this purpose?

Any tip would be highly appreciated.

Ta,
DanB


Bellow the traces for initial SUBSCRIBEs as well as in-dialog ones (info 
mangled to protect privacy).

#####################################
Normally routed request (non-dialog one, correctly bridged)
#####################################

"""
#
U 2014/11/12 19:04:51.293887 pub_ip_ua:54705 -> pub_ip_ep:5060
SUBSCRIBE sip:user1 at fakedomain.com:5060 SIP/2.0.
Via: SIP/2.0/UDP 192.168.243.82:5062;branch=z9hG4bK1114302228.
From: "user2" <sip:user2 at fakedomain.com>;tag=1003326118.
To: <sip:user1 at fakedomain.com>.
Call-ID: 1273081718.
CSeq: 2 SUBSCRIBE.
Contact: <sip:user2 at 192.168.243.82:5062>.
Accept: application/dialog-info+xml.
Max-Forwards: 70.
User-Agent: Tiptel IP 284 6.70.13.18 0015651b574f.
Expires: 60.
Event: dialog.
Content-Length: 0.
.

#
T 2014/11/12 19:04:51.295706 pub_ip_ep:34052 -> 192.168.51.168:5060 [AP]
SUBSCRIBE sip:user1 at 192.168.51.168:5060;transport=tcp SIP/2.0.
Record-Route: <sip:pub_ip_ep;transport=tcp;r2=on;lr;nat=yes>.
Record-Route: <sip:pub_ip_ep;r2=on;lr;nat=yes>.
Via: SIP/2.0/TCP 
pub_ip_ep;branch=z9hG4bKe26f.3dce66bd1976447b88f6096e926ce68c.0.
Via: SIP/2.0/UDP 
192.168.243.82:5062;rport=54705;received=pub_ip_ua;branch=z9hG4bK1114302228.
From: "user2" <sip:user2 at fakedomain.com>;tag=1003326118.
To: <sip:user1 at fakedomain.com>.
Call-ID: 1273081718.
CSeq: 2 SUBSCRIBE.
Contact: <sip:user2 at 192.168.243.82:5062;alias=pub_ip_ua~54705~1>.
Accept: application/dialog-info+xml.
Max-Forwards: 65.
User-Agent: Tiptel IP 284 6.70.13.18 0015651b574f.
Expires: 60.
Event: dialog.
Content-Length: 0.
.

#
T 2014/11/12 19:04:51.300350 192.168.51.168:5060 -> pub_ip_ep:34052 [AP]
SIP/2.0 202 Accepted.
Via: SIP/2.0/TCP 
pub_ip_ep;branch=z9hG4bKe26f.3dce66bd1976447b88f6096e926ce68c.0;rport=34052.
Via: SIP/2.0/UDP 
192.168.243.82:5062;rport=54705;received=pub_ip_ua;branch=z9hG4bK1114302228.
Record-Route: <sip:pub_ip_ep;transport=tcp;r2=on;lr;nat=yes>.
Record-Route: <sip:pub_ip_ep;r2=on;lr;nat=yes>.
From: "user2" <sip:user2 at fakedomain.com>;tag=1003326118.
To: <sip:user1 at fakedomain.com>;tag=PFxfnedC0jP7.
Call-ID: 1273081718.
CSeq: 2 SUBSCRIBE.
Contact: <sip:user1 at 192.168.51.168:5060>.
Expires: 60.
User-Agent: Sipean-AS 1.2.10.
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, 
REGISTER, REFER, NOTIFY, PUBLISH, SUBSCRIBE.
Supported: timer, path, replaces.
Allow-Events: talk, hold, conference, presence, as-feature-event, 
dialog, line-seize, call-info, sla, include-session-description, 
presence.winfo, message-summary, refer.
Subscription-State: active;expires=60.
Content-Length: 0.
.

##
U 2014/11/12 19:04:51.300745 pub_ip_ep:5060 -> pub_ip_ua:54705
SIP/2.0 202 Accepted.
Via: SIP/2.0/UDP 
192.168.243.82:5062;rport=54705;received=pub_ip_ua;branch=z9hG4bK1114302228.
Record-Route: <sip:pub_ip_ep;transport=tcp;r2=on;lr;nat=yes>.
Record-Route: <sip:pub_ip_ep;r2=on;lr;nat=yes>.
From: "user2" <sip:user2 at fakedomain.com>;tag=1003326118.
To: <sip:user1 at fakedomain.com>;tag=PFxfnedC0jP7.
Call-ID: 1273081718.
CSeq: 2 SUBSCRIBE.
Contact: <sip:user1 at 192.168.51.168:5060>.
Expires: 60.
User-Agent: Sipean-AS 1.2.10.
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, 
REGISTER, REFER, NOTIFY, PUBLISH, SUBSCRIBE.
Supported: timer, path, replaces.
Allow-Events: talk, hold, conference, presence, as-feature-event, 
dialog, line-seize, call-info, sla, include-session-description, 
presence.winfo, message-summary, refer.
Subscription-State: active;expires=60.
Content-Length: 0.
"""





######################
NOT BRIDGED, IN-DIALOG requests:
######################

"""
#
U 2014/11/12 19:46:18.448550 pub_ip_ua:54705 -> pub_ip_ep:5060
SUBSCRIBE sip:user1 at 192.168.51.168:5060 SIP/2.0.
Via: SIP/2.0/UDP 192.168.243.82:5062;branch=z9hG4bK459444805.
Route: <sip:pub_ip_ep;r2=on;lr;nat=yes>.
Route: <sip:pub_ip_ep;transport=tcp;r2=on;lr;nat=yes>.
From: "user2" <sip:user2 at fakedomain.com>;tag=1902678123.
To: <sip:user1 at fakedomain.com>;tag=2518urgZJFet.
Call-ID: 2104228355.
CSeq: 3 SUBSCRIBE.
Contact: <sip:user2 at 192.168.243.82:5062>.
Accept: application/dialog-info+xml.
Max-Forwards: 70.
User-Agent: Tiptel IP 284 6.70.13.18 0015651b574f.
Expires: 60.
Event: dialog.
Content-Length: 0.
.

#
U 2014/11/12 19:46:18.449161 pub_ip_ep:5060 -> 192.168.51.168:5060
SUBSCRIBE sip:user1 at 192.168.51.168:5060 SIP/2.0.
Via: SIP/2.0/UDP 
pub_ip_ep;branch=z9hG4bK7de2.a9aed4070706f93b25b4d2d3d7963a19.0.
Via: SIP/2.0/UDP 
192.168.243.82:5062;rport=54705;received=pub_ip_ua;branch=z9hG4bK459444805.
From: "user2" <sip:user2 at fakedomain.com>;tag=1902678123.
To: <sip:user1 at fakedomain.com>;tag=2518urgZJFet.
Call-ID: 2104228355.
CSeq: 3 SUBSCRIBE.
Contact: <sip:user2 at 192.168.243.82:5062;alias=pub_ip_ua~54705~1>.
Proxy-Authorization: Digest username="user2", realm="fakedomain.com", 
nonce="VGOr71RjqsMDoDyEqMnELO4fotFJLYhV", 
uri="sip:user1 at 192.168.51.168:5060", 
response="12fbfa50428b37bd55dbb4b51f8d5cba", algorithm=MD5.
Accept: application/dialog-info+xml.
Max-Forwards: 65.
User-Agent: Tiptel IP 284 6.70.13.18 0015651b574f.
Expires: 60.
Event: dialog.
Content-Length: 0.
"""