New subject: Best way to handle OPTIONS message with Max-Forwards of 0

9 Jun 2011

Thanks for the reply.

In our case, the SBC treated the 483 as an error of some sort and wouldn't send
traffic.  It wanted a 200/OK.

Anyway, I thought that when a proxy responds to an OPTIONS, its supposed to
answer with a 200/OK (3261 11.2).  Is that correct?

Sean O'Donnell

---- On Wed, 8 Jun 2011, Klaus Darilion (klaus.mailinglists(a)pernau.at) wrote:

What is the problem with the default config?

The proxy will respond with 483 as the standard defines. I guess the SBC
will doe this to check if the proxy is alive and will accept any
response as "the proxy is alive".

regards
Klaus

Am 08.06.2011 18:28, schrieb Sean O'Donnell:
...
  Hi:

 We're running kamailio 1.5.5 as part of our VoIP infrastructure.  One of our
 service providers
 has an SBC that sends an OPTIONS messages with a Max-Forwards of 0.

 Looking at RFC 3261 section 11, this seems to be a valid method of forcing the
 proxy to respond to the OPTIONS.
 However, the standard initial sanity checks in most proxy configs will reject
 this message.  I fixed our script
 by changing to this:

         # initial sanity checks -- messages with
         # max_forwards==0, or excessively long requests
         if (!mf_process_maxfwd_header("10")) {
                 if( method != "OPTIONS" ) {
                         sl_send_reply("483","Too Many Hops");
                         return;
                 };
         };
         if ( msg:len > max_len ) {
                 sl_send_reply("513", "Message too big");
                 return;
         };

 but does anyone have a better solution?

 Thanks,

 Sean O'Donnell

 _______________________________________________
 SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
 sr-users(a)lists.sip-router.org
 http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users 
_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users(a)lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users

Re: [SR-Users] Best way to handle OPTIONS message with Max-Forwards of 0