29 Sep
2004
29 Sep
'04
9:19 a.m.
Hi All,
I have a question regarding the functioning of the Iptel proxy server. As
far as I know, only when there is "rports" field present in the "via"
header field in a SIP request(INVITE for ex.), the proxy server should send
the responses to the source port from which the request is sent. I would
like to know if there is any other case in which the responses are sent to
the source port instead of the VIA port.
Please provide me with the details on this.
thanks
Mahesh
29 Sep
29 Sep
1:35 p.m.
On Sep 29, 2004 at 11:49, mahesh <mahesha(a)intoto.com> wrote:
Hi All,
I have a question regarding the functioning of the Iptel proxy server. As
far as I know, only when there is "rports" field present in the "via"
header field in a SIP request(INVITE for ex.), the proxy server should send
the responses to the source port from which the request is sent. I would
like to know if there is any other case in which the responses are sent to
the source port instead of the VIA port.
No, for UDP there isn't (if no rport is present and you don't use
force_rport() in your config, the response is sent to the via port if
present and if not, to 5060).
For TCP, ser will always try to reuse the original connection, so if the
connection on which it received the request is still up, it will send
the reply back on it.
Andrei
1 Oct
1 Oct
7:46 a.m.
Hi Andrei,
Thanks for the reply.
I am using the publicly available iptel proxy server(195.37.77.99) to test
my implementation of SIP-ALG. I am using the following configuration
HOST1(winXP)---FW---Internet---HOST2(winCP)
FW is the firewall/NAT device, which has the ALG implementation. I am using
SJPhone on my hosts to communicate using SIP(UDP). I observe that the
responses to requests sent by HOST1 come from the proxy(iptel) to the
source port(of FW), from which the request was sent, instead of on VIA.
There is no "rport" field in the VIA header field of the request.
Does anyone know if the iptel proxy server is configured to use "force_rport".
thanks
Mahesh
On Sep 29, 2004 at 11:49, mahesh
<mahesha(a)intoto.com> wrote:
Hi All,
I have a question regarding the functioning of the Iptel proxy server. As
far as I know, only when there is "rports" field present in the
"via"
header field in a SIP request(INVITE for ex.), the proxy server should
send
the responses to the source port from which the
request is sent. I would
like to know if there is any other case in which the responses are sent to
the source port instead of the VIA port.
No, for UDP there isn't (if no rport is present and you don't use
force_rport() in your config, the response is sent to the via port if
present and if not, to 5060).
For TCP, ser will always try to reuse the original connection, so if the
connection on which it received the request is still up, it will send
the reply back on it.
Andrei
6:29 p.m.
On Oct 01, 2004 at 10:16, mahesh <mahesha(a)intoto.com> wrote:
Hi Andrei,
Thanks for the reply.
I am using the publicly available iptel proxy server(195.37.77.99) to test
my implementation of SIP-ALG. I am using the following configuration
HOST1(winXP)---FW---Internet---HOST2(winCP)
FW is the firewall/NAT device, which has the ALG implementation. I am using
SJPhone on my hosts to communicate using SIP(UDP). I observe that the
responses to requests sent by HOST1 come from the proxy(iptel) to the
source port(of FW), from which the request was sent, instead of on VIA.
There is no "rport" field in the VIA header field of the request.
Does anyone know if the iptel proxy server is configured to use
"force_rport".
Yes, it is.
Andrei
5 Oct
5 Oct
12:18 p.m.
Andrei,
Any significant reason on why this is being done??
Mahesh
At 08:59 PM 10/1/2004, Andrei Pelinescu-Onciul wrote:
On Oct 01, 2004 at 10:16, mahesh
<mahesha(a)intoto.com> wrote:
Hi Andrei,
Thanks for the reply.
I am using the publicly available iptel proxy server(195.37.77.99) to test
my implementation of SIP-ALG. I am using the following configuration
HOST1(winXP)---FW---Internet---HOST2(winCP)
FW is the firewall/NAT device, which has the ALG implementation. I am
using
SJPhone on my hosts to communicate using
SIP(UDP). I observe that the
responses to requests sent by HOST1 come from the proxy(iptel) to the
source port(of FW), from which the request was sent, instead of on VIA.
There is no "rport" field in the VIA header field of the request.
Does anyone know if the iptel proxy server is configured to use
"force_rport".
Yes, it is.
Andrei 
12:29 p.m.
Hi Mahesh,
force_rport() is used as a part of the NAT traversal solution. When a
request come across a NAT, the server will see a different port (the one
of the NAT), instead of the one advertise in VIA. And to be able to pass
the reply back to UAC (through NAT), the server MUST use the detected
NAT port (otherwise the NAT will not allow the message to pass).
best regards,
Marian
mahesh wrote:
Andrei,
Any significant reason on why this is being done??
Mahesh
At 08:59 PM 10/1/2004, Andrei Pelinescu-Onciul wrote:
On Oct 01, 2004 at 10:16, mahesh
<mahesha(a)intoto.com> wrote:
_______________________________________________
Serusers mailing list
serusers(a)lists.iptel.org
http://lists.iptel.org/mailman/listinfo/serusers
Hi Andrei,
Thanks for the reply.
I am using the publicly available iptel proxy server(195.37.77.99)
to test
my implementation of SIP-ALG. I am using the
following configuration
HOST1(winXP)---FW---Internet---HOST2(winCP)
FW is the firewall/NAT device, which has the ALG implementation. I
am using
SJPhone on my hosts to communicate using
SIP(UDP). I observe that the
responses to requests sent by HOST1 come from the proxy(iptel) to the
source port(of FW), from which the request was sent, instead of on
VIA.
There is no "rport" field in the VIA
header field of the request.
Does anyone know if the iptel proxy server is configured to use
"force_rport".
Yes, it is.
Andrei
12:32 p.m.
On Oct 05, 2004 at 14:48, mahesh <mahesha(a)intoto.com> wrote:
Andrei,
Any significant reason on why this is being done??
Because there are a lot of broken UAs not including rport in their Vias
and probably all UAs are symmetric these days.
Andrei
At 08:59 PM 10/1/2004, Andrei Pelinescu-Onciul wrote:
On Oct 01, 2004 at 10:16, mahesh
<mahesha(a)intoto.com> wrote:
Hi Andrei,
Thanks for the reply.
I am using the publicly available iptel proxy server(195.37.77.99) to
test
my implementation of SIP-ALG. I am using the
following configuration
HOST1(winXP)---FW---Internet---HOST2(winCP)
FW is the firewall/NAT device, which has the ALG implementation. I am
using
SJPhone on my hosts to communicate using
SIP(UDP). I observe that the
responses to requests sent by HOST1 come from the proxy(iptel) to the
source port(of FW), from which the request was sent, instead of on VIA.
There is no "rport" field in the VIA header field of the request.
Does anyone know if the iptel proxy server is configured to use
"force_rport".
Yes, it is.
Andrei 
12:46 p.m.
At 11:18 AM 10/5/2004, mahesh wrote:
Andrei,
Any significant reason on why this is being done??
yes. to make sure that majority of devices that are symmetric but
are silly not to advertise it using rport work. It will fail
for those which are not symmetric -- I am not worried about
them too much, they should be.
-jiri
Mahesh
At 08:59 PM 10/1/2004, Andrei Pelinescu-Onciul wrote:
--
Jiri Kuthan http://iptel.org/~jiri/
On Oct 01, 2004 at 10:16, mahesh
<mahesha(a)intoto.com> wrote:
_______________________________________________
Serusers mailing list
serusers(a)lists.iptel.org
http://lists.iptel.org/mailman/listinfo/serusers Hi Andrei,
Thanks for the reply.
I am using the publicly available iptel proxy server(195.37.77.99) to test
my implementation of SIP-ALG. I am using the following configuration
HOST1(winXP)---FW---Internet---HOST2(winCP)
FW is the firewall/NAT device, which has the ALG implementation. I am using
SJPhone on my hosts to communicate using SIP(UDP). I observe that the
responses to requests sent by HOST1 come from the proxy(iptel) to the
source port(of FW), from which the request was sent, instead of on VIA.
There is no "rport" field in the VIA header field of the request.
Does anyone know if the iptel proxy server is configured to use
"force_rport".
Yes, it is.
Andrei
7353
days inactive
7359
days old
7 comments
4 participants
participants (4)
-
Andrei Pelinescu-Onciul -
Jiri Kuthan -
mahesh -
Marian Dumitru