Re: SCTP Abort

Hi Ashish,

I do not see any management messages sent on stream 1...

The SCTP implementations are pretty outdated... The one
of the softswitch includes a single IP address in the
INIT chunk and it uses the Adler checksum. Not sure whether
the SCTP stack of the SG just adopts to it.

I'm not sure how good the SCTP stack of the SG is, but
the T-bit is set in all ABORTs. If the stack is correct,
it means that it has no state about the association.

This would mean that it responds to an ASPUP with an
ASPUP-ACK and removes the state at the M3UA and SCTP
layer without notifying the peer. The ABORTs are in
response to incoming packets when the state is already
gone.

Best regards
Michael

On Feb 26, 2009, at 4:34 PM, Ashish_Soregaonkar wrote:

>
> Arvind,
>
> Have you noticed that the SG is aborting the association in response  
> to management messages sent on stream 1. While for similar  
> management messages on stream 0 it replies with the expected  
> response. Though M3UA Error is expected here as per RFC 4333 & 3332.
>
> I agree with Brian. It would be better to check the conformance of  
> you SCTP implementation.
>
> HTH,
> _Ashish
>
> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On  
> Behalf Of Brian F. G. Bidulock
> Sent: Thursday, February 26, 2009 8:50 PM
> To: Arvind Kumar
> Cc: [email protected]
> Subject: Re: [Sigtran] SCTP Abort
>
> Arvind,
>
> Your log file shows both implementations using
> Adler32 checksum.  The checksum was updated to
> CRC32c some years ago, why is it using Adler32?
>
> That is: a conforming SCTP configuration might
> be a better place to start...
>
> --brian
>
> Arvind Kumar wrote:                          (Thu, 26 Feb 2009  
> 14:09:46)
>>
>>   Hello Sigtran Gurus!
>>   I am bringing Signaling Gateway Stack with Softswitch as follows:
>>              Signaling Gateway -------------          Softswitch
>>              192.168.103.160
>>   192.168.103.170
>>       Association is established then goes down, softswitch  
>> establishes
>>   the association (four way handshake), it brings up the association,
>>   but suddenly Signaling Gateway is aborting the association by  
>> sending
>>   SCTP ABORT. This is happening again and again.
>>   Surprising thing is that there is no reason in  ABORT msg.
>>   Could you please give me any clue regarding this.
>>   I have attached the log.
>>   Thanks & Regards,
>>   Arvind
>
>
>> _______________________________________________
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>> https://www.ietf.org/mailman/listinfo/sigtran
>
>
> -- 
> Brian F. G. Bidulock
> [email protected]
> http://www.openss7.org/
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