[SR-Users] Lifetime of Invite with no Ack

[Duarte Rocha]

Thanks for the reply.

Here is my scenario :


Client________Kamailio______Destination_1____Destination_2
  |_____INV_______|_______________|_______________|
  |---------------------->|______INV______|_______________|
  |_______________|---------------------->|_______________|
  |_______________|_______________|_______________|
  |_______________|____200_OK_____|_______________|
  |_______________|<-----------------------|_______________|
  |____200_OK_____|_______________|_______________|
  |<-----------------------|_______________|_______________|

  |_______________|_______________|_______________|
  |___INV(Retr)____|_______________|_______________|
  |---------------------->|______INV______|_______________|

  |_______________|------------------------------------------------>|


  |_______________|_______________|_______________|




As you can see, the client never sends the ACK to Kamailio and retransmits
the first INVITE (No To-TAG) again after more than 5s. After this Kamailio
uses Dispatcher to send to a destination from a group and chooses
Destination_2.

Since the INVITE is sent to Destination_2, my system treats this as a
second call being created.

Should this scenario happen under the SIP stack rules? Shouldn't Kamailio
send a "491 - Request Pending" on this scenario?

If not, how i can configure Kamailio to behave like that? In my code i have
the following conditions for a Request to able to be sent by DISPATCHER :

                - if( is_method("INVITE") && !has_totag() )

                - if(!t_check_trans())

                What other conditions can i setup in order for this INVITE
to be treated like a retransmission or being rejected?

Best Regards,

A segunda, 13/04/2020, 13:31, Daniel-Constantin Mierla <miconda at gmail.com>
escreveu:

> By default the transaction that gets a final reply is kept for another
> 5sec or so in memory to deal with retranmissions, etc ... There is a
> wait_timer parameter in tm module.
>
> The ACK after 200ok is separate transaction and has no influence on INVITE
> transaction. For the ACK after 300+ reply, there should be some
> retransmissons of the reply in the INVITE transaction.
>
> The dialog module is influenced by the missing ACK after 200ok.
>
> Cheers,
> Daniel
> On 13.04.20 13:18, Duarte Rocha wrote:
>
> Sorry i didn't specify.
>
> It is after the 200 Ok. Will it be different in a reply greater than 300?
>
> Best regards
>
> A segunda, 13/04/2020, 12:16, Daniel-Constantin Mierla <miconda at gmail.com>
> escreveu:
>
>> Hello,
>>
>> is it about ACK after 200ok or the ACK after 300 or greater reply?
>>
>> Cheers,
>> Daniel
>> On 13.04.20 13:04, Duarte Rocha wrote:
>>
>> Greetings,
>>
>> How much time will Kamailio keep a transaction active if the ACK to a
>> INVITE is never received by Kamailio?
>>
>> Best Regards,
>>
>> _______________________________________________
>> Kamailio (SER) - Users Mailing Listsr-users at lists.kamailio.orghttps://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
>>
>> --
>> Daniel-Constantin Mierla -- www.asipto.comwww.twitter.com/miconda -- www.linkedin.com/in/miconda
>>
>> --
> Daniel-Constantin Mierla -- www.asipto.comwww.twitter.com/miconda -- www.linkedin.com/in/miconda
>
>
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