Subject: [Sigtran] Doubt regarding SCTP TSN/SSN

From: Nagesh <[email-masked]>
Date: Tue, 01 Sep 2009 17:43:57 +0530

Hi Group,

      I have a following doubt regarding SCTP TSN/SSN Handling. 

    SCTP
SCTP

(Peer Node)
(Local Node)

                     Association is established with Local Init TSN = 0

<---------------------------------------------------------------------------
---------------------->

                                          DATA1

----------------------------------------------------------------------------
----------------------->     

                        TSN(0)     SSN(0)   StreamId = 0

                                          DATA2

----------------------------------------------------------------------------
----------------------->     

                        TSN(2)     SSN(1)   StreamId = 0

                                          DATA3

----------------------------------------------------------------------------
----------------------->     

                        TSN(1)     SSN(2)   StreamId = 0

                                          DATA4

----------------------------------------------------------------------------
----------------------->     

                        TSN(2)     SSN(3)   StreamId = 0

                                          DATA5

----------------------------------------------------------------------------
----------------------->     

                        TSN(3)     SSN(3)   StreamId = 0

            What should be the behavior when we receive DATA4 and DATA5
since the SSN is in sequence but the TSN is out-of-order?

     Request you to please clarify my doubt.

Thanks and Regards,

Nagesh.

****************************************************************************
***********************************************
           This e-mail and attachments contain confidential information from
HUAWEI, which is intended only for the person or entity whose address is
listed above. Any use of the information contained herein in any way
(including, but not limited to, total or partial disclosure, reproduction,
or dissemination) by persons other than the intended recipient's) is
prohibited. If you receive this e-mail in error, please notify the sender by
phone or email immediately and delete it!

---

From: Michael Tüxen <[email-masked]>
Date: Tue, 1 Sep 2009 16:41:22 +0200

>       I have a following doubt regarding SCTP TSN/SSN Handling.
Hi,

please note that SCTP is now handled at [email-masked].
> (Peer  
> Node 
> )                                                                                                       (Local 
>  Node)
> ß 
> ---------------------------------------------------------------------------------------------à
>                                           DATA1
>                    
> -------------------------------------------------------------------------------------------------à
> -------------------------------------------------------------------------------------------------à
> -------------------------------------------------------------------------------------------------à
This assignment is broken, since the TSN of SSN(1) should be smaller  
than the
one of SSN(2).
>
>                                           DATA4
>                    
> -------------------------------------------------------------------------------------------------à
So you are resusing TSN(2) here? It will be dropped, since it was  
already received.
>
>                                           DATA5
>                    
> -------------------------------------------------------------------------------------------------à
>             What should be the behavior when we receive DATA4 and  
> DATA5 since the SSN is in sequence but the TSN is out-of-order?
>
> ***************************************************************************************************************************
>            This e-mail and attachments contain confidential  
> information from HUAWEI, which is intended only for the person or  
> entity whose address is listed above. Any use of the information  
> contained herein in any way (including, but not limited to, total or  
> partial disclosure, reproduction, or dissemination) by persons other  
> than the intended recipient's) is prohibited. If you receive this e- 
> mail in error, please notify the sender by phone or email  
> immediately and delete it!
>
>
> _______________________________________________
> Sigtran mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/sigtran