24 May 2013 07:47
21 May 2013 11:22
Re: Query for "received" parameter in top Via header
Olle E. Johansson <oej <at> edvina.net>
2013-05-21 09:22:38 GMT
2013-05-21 09:22:38 GMT
21 maj 2013 kl. 11:19 skrev isshed <isshed.sip <at> gmail.com>: > Anand > > the received parameter is added by your own stack(one who received the > request). It contains real IP from where the packet is received. In case of > NAT it will be NAT IP. That seems like a broken NAT. If you are inside of a NAT and receive a message from the outside, the NAT should not change the sender's address, right? /O > > On Tue, May 21, 2013 at 2:35 PM, ANAND KUMAR <ss1439anand <at> yahoo.co.in>wrote: > >> Section 18.2.2 Sending Responses (For servers) of rfc3261 says: >> >> if the top Via has a "received" parameter, the response MUST be sent to >> the address in the "received" parameter, using the port indicated in the >> "sent-by" value, or using port 5060 if none is specified explicitly. If >> this fails, for example, elicits an ICMP "port unreachable" response >> >> >> Now assume a Client (which is behind a proxy and there may be a NAT >> between the client and proxy) which is in a 2-way call receives BYE for >> this call (I am assuming UAS behaviour by the Client) having top Via header >> with received parameter (having ip address which is not same as that of the >> proxy). >> >> My query:(Continue reading)
21 May 2013 11:05
Query for "received" parameter in top Via header
ANAND KUMAR <ss1439anand <at> yahoo.co.in>
2013-05-21 09:05:10 GMT
2013-05-21 09:05:10 GMT
Section 18.2.2 Sending Responses (For servers) of rfc3261 says: if the top Via has a "received" parameter, the response MUST be sent to the address in the "received" parameter, using the port indicated in the "sent-by" value, or using port 5060 if none is specified explicitly. If this fails, for example, elicits an ICMP "port unreachable" response Now assume a Client (which is behind a proxy and there may be a NAT between the client and proxy) which is in a 2-way call receives BYE for this call (I am assuming UAS behaviour by the Client) having top Via header with received parameter (having ip address which is not same as that of the proxy). My query: 1. Then should this Client send 200 OK of BYE to this ip address (received)? 2. Will this scenario ever happen for the client (also assume a NAT between the Client and proxy for the purpose of analysis) in realtime? 3. If this scenario will never happen in real time then does the RFC statement(written above) stands valid for this Client (UAS in this case)? Please correct my understanding if it is wrong somewhere. Thanks in advance Anand Kumar
20 May 2013 21:49
20 May 2013 20:12
Query regarding session timer behaviour in SIP Stack
Priya Arya <priya.arya <at> aricent.com>
2013-05-20 18:12:49 GMT
2013-05-20 18:12:49 GMT
Hi All,
I have certain queries about the session timer behaviour in the SIP Stack.
The scenario is as follows :
SIP Stack N/w
At T0s
INVITE -------------------------------------------------------------------------------->
(having SE=600 &Min-SE = 600 )
100 Trying <---------------------------------------------------------------------------
180 Ringing <-------------------------------------------------------------------------
200 OK <-------------------------------------------------------------------------------
(having Require:timer,SE=600,refresher=uas)
ACK ---------------------------------------------------------------------------------->
<---------------------------------Call Connected --------------------------------->
At this point the Call is connected and the session timer is started by SIP Stack when 200 OK from the Network
is received by the SIP Stack.
After this, SIP Stack sends out a Re-INVITE with as the new offer(as the version number in the o-line is
incremented here).
At T0+8s
INVITE --------------------------------------------------------------------------->
(Version number in o-line of Re-INVITE SDP is incremented by 1)
200 OK <-------------------------------------------------------------------------------
(having SE=19200,refresher=uas)
(Continue reading)
20 May 2013 12:53
Query for method name in Request URI
ANAND KUMAR <ss1439anand <at> yahoo.co.in>
2013-05-20 10:53:36 GMT
2013-05-20 10:53:36 GMT
Hi, I have a query for method available in Request URI. According to rfc 3261 section 19.1.5 "If the URI contains a method parameter, its value MUST be used as the method of the request." Now suppose the UAC receives 302 Moved Temporary with Contact like sip:biloxi.com;method=REGISTER;transport=tcp?to=sip:bob%40biloxi.com Doest that mean the UAC need to send REGISTER request to sip:biloxi.com ? If not then what is the meaning of this method name in the Request URI? Thanks & Regards Anand Kumar
20 May 2013 12:37
FMT are mandatory in the Media Descriptions ("m=") line
Aman <amanpreeet.singh <at> gmail.com>
2013-05-20 10:37:56 GMT
2013-05-20 10:37:56 GMT
Hi All, Looking for the views on, if the media format description <fmt> are mandatory to mention in the media descriptions (m=) line of SDPs. RFC4566 section 8.2.3 says, ... RTP payload formats under the "RTP/AVP" and "RTP/SAVP" profiles MUST use the payload type number as their "fmt" value. ... how a state-full proxy/SBC should react, who is receiving the m= line having no fmt values like, |v=0 |o=ABC-SIP 2000 1000 IN IP4 192.168.180.10 |s=SIP Call |c=IN IP4 192.168.180.10 |t=0 0 |m=audio 25218 RTP/AVP |a=sendrecv |a=rtpmap:0 PCMU/8000 |a=ptime:20 Cheers, Aman
17 May 2013 18:59
Survey on SIP overload control algorithms
Yang Hong <yang_hong <at> hotmail.com>
2013-05-17 16:59:46 GMT
2013-05-17 16:59:46 GMT
Hello Folks. SIP faces with overload issue recently due to its popularity. Build-in overload mechanism cannot prevent overload effectively. Therefore, IETF SIP Overload Control (soc) Working Group works on IETF RFC "SIP Overload Control" currently. http://tools.ietf.org/html/draft-ietf-soc-overload-control-12 A survey on SIP overload control algorithms (including IETF RFC "SIP Overload Control") can be downloaded from the following link free of charge. Y. Hong, C. Huang, and J. Yan, “A Comparative Study of SIP Overload Control Algorithms,"Network and Traffic Engineering in Emerging Distributed Computing Applications, Edited by J. Abawajy, M. Pathan, M. Rahman, A.K. Pathan, and M.M. Deris, IGI Global, 2012, pp. 1-20. http://www.researchgate.net/publication/231609451_A_Comparative_Study_of_SIP_Overload_Control_Algorithms http://arxiv.org/abs/1210.1505 http://www.igi-global.com/chapter/comparative-study-sip-overload-control/67496 Control theorectic approaches have been applied to model the interactions between an overloaded SIP server and its upstream servers as a feedback control system in two different scenarios - redundant retransmission ratio control and round trip delay control (IEEE Globecom 2010 and ICC 2011). "Mitigating SIP Overload Using a Control-Theoretic Approach" IEEE Globecom 2010 http://www.researchgate.net/publication/221284946_Mitigating_SIP_Overload_Using_a_Control-Theoretic_Approach http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5683124&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5683124 Implementation of implicit SIP overload control in the real system "An Efficient Earthquake Early Warning Message Delivery Algorithm Using an in Time Control-Theoretic Approach" http://link.springer.com/chapter/10.1007%2F978-3-642-23641-9_15# http://www.ipv6.org.tw/docu/elearning8_2011/1010004798p_3-7.pdf "Design Of A PI Rate Controller for Mitigating SIP Overload" IEEE ICC 2011(Continue reading)
15 May 2013 22:04
Clarification/recommendation needed on sip protocol
Yulian Oifa <oifa.yulian <at> gmail.com>
2013-05-15 20:04:16 GMT
2013-05-15 20:04:16 GMT
Hello to all. I am working with jain sip based software and having the following issue: while proxy sends sip MESSAGE request to UA transaction can be timed out but message still delivered. This may happen on any kind of channel due to network slow response,and on tls/tcp channel due to connection oriented nature of channel. in case of tls/tcp message is stored in socket buffer and socket tries to resend this packet. When first time it tries to send the packet destination is not reachable due to firewall/nat machine on the way to UA which removed the nat hole. After some time UA will send either keepalive or some sip request and this will cause nat hole to be reopened. Since proxy socket received the data from UA it will resend all the data it has for him in buffer and message will be delivered. UA of course will send 200 OK for the message , but since transaction timed out this response can not be send further. Since B2BUA will try to send same sip message later on , UA will end up with 2 or more duplicate messages received. Similar situation may happen with any NON INVITE transaction. Is there some rfc or some recommendation how this issue can be resolved? Thanks and best regards Yulian Oifa Sipme LTD israel
14 May 2013 12:25
Require header in ACK request
Sumant Gupta <sumantgupta <at> gmail.com>
2013-05-14 10:25:42 GMT
2013-05-14 10:25:42 GMT
Hi All, As per 3261 "An ACK request for a 2xx response MUST contain only those Require and Proxy-Require values that were present in the initial request". As per table 2 (rfc 3261) require header is not applicable in ACK request. Does it serve any purpose if we send Require/Proxy-Require header in the ACK request? Any reason why it is mentioned in RFC as older posts on this forum does not provide any concrete answer? Regards Sumant
14 May 2013 08:25
Query for Out of dialod Notify
Gaurav Gupta <gaurav7.gupta <at> aricent.com>
2013-05-14 06:25:42 GMT
2013-05-14 06:25:42 GMT
Hi, Subscribe creates a dialog in SIP, then why client can receive out of dialog notify Thanks Gaurav Gupta =============================================================================== Please refer to http://www.aricent.com/legal/email_disclaimer.html for important disclosures regarding this electronic communication. ===============================================================================
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