[OpenSIPS-Users] confusion with forking

[Jeff Pyle]

Toyima,

Here's how I think of it (100% accuracy not guaranteed!).  Imagine the following scenarios.

An INVITE comes into Opensips.  Opensips then sends it out to 5 places at once.  Once it receives a 200 OK from one of those 5 places, it sends CANCELs to the other 4.  This is parallel forking – where the proxy sends to multiple upstream destinations at once.  This is achieved by having multiple Contacts loaded before a t_relay.

An INVITE comes into Opensips.  Opensips sends it to the first destination, but this destination doesn't answer or replies with some other negative response.  In fact, not answering is a negative response (408 Timeout) within Opensips.  Openisps catches this negative response in a failure_route and tries to send the INVITE to a second destination, and so on.  This is serial forking, one at a time.  This is achieved by intention scripting to catch a failure in a failure_route and handle it as you see fit.

Forking in general seems to me to be more a description of a process rather than a specific set of functions in Opensips.  There are various ways to implement either flavor of it, depending on your specific needs.


- Jeff



From: Toyima Dias <toyimads at gmail.com<mailto:toyimads at gmail.com>>
Reply-To: OpenSIPS users mailling list <users at lists.opensips.org<mailto:users at lists.opensips.org>>
Date: Fri, 28 Jan 2011 04:39:10 -0500
To: OpenSIPS users mailling list <users at lists.opensips.org<mailto:users at lists.opensips.org>>
Subject: [OpenSIPS-Users] confussion with forking

Hello,

I'm a little confuse about the parallel and serial forking...whats the meaning of that? is this like a t_replicate function works? I can make that 2 phones ring if the are registered with the same AOR...is that forking? but serial or parallel? what about serialize_branches(clear), next_branches() and append_branches() functions?

Thanks in advance for your help!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensips.org/pipermail/users/attachments/20110128/0825af18/attachment.htm>