Re: Abort chunk bundled with data chunk

On Oct 15, 2009, at 11:06 AM, Salil Agrawal wrote:

> Thanks Ashwani,
>
> That means if we receive any DATA chunk in a packet then we first need
> to check if this packet contains the ABORT or not before sending the
> SACK. If packet is not containing the ABORT then only SACK will we  
> sent
> otherwise not.
I would just start processing the packet, process the DATA chunk,
find the ABORT, decide the packet is illegal, discard the association,
and do not send an ABORT since I received one.

Best regards
Michael
> Also if this is going to be expected behavior then it would impact the
> protocol performance as we need to traverse the whole packet before
> sending any SACK.
>
> Thanks,
> Salil
>
>
>
> -----Original Message-----
> From: Ashwani Kathuria [mailto:[email protected]]
> Sent: Thursday, October 15, 2009 2:30 PM
> To: Salil Agrawal
> Cc: [email protected]
> Subject: Re: [Sigtran] Abort chunk bundled with data chunk
>
> No, SACK should not be sent in such case.
>
> On Thu, Oct 15, 2009 at 2:28 PM, Salil Agrawal  
> <[email protected]>
> wrote:
>> Hi Ashwani,
>>
>> The question is not that whether DATA chunk should be bundled with  
>> the
>> ABORT or not. RFC is very clear about it that the sender should not  
>> do
>> in that way but here the question is if we at the receiver end
> receives
>> the same then what should be the action at the receiver end (should  
>> we
>> send the SACK for the DATA or not).
>>
>> Thanks,
>> Salil
>>
>> -----Original Message-----
>> From: Ashwani Kathuria [mailto:[email protected]]
>> Sent: Thursday, October 15, 2009 2:11 PM
>> To: Salil Agrawal
>> Cc: [email protected]
>> Subject: Re: [Sigtran] Abort chunk bundled with data chunk
>>
>> Placing DATA chunk before control chunk (ABORT) makes it an Invalid
> SCTP
>> packet.
>>
>> --Ashwani Kathuria
>>
>> On Thu, Oct 15, 2009 at 1:46 PM, Salil Agrawal
> <[email protected]>
>> wrote:
>>> Thanks Ashwani,
>>>
>>> I understand that it does not make any sense to send the SACK, and
>> abort
>>> chunk should be the placed before the DATA chunk. But the question  
>>> is
>> if
>>> the ABORT chunk is placed after the DATA chunk in the received  
>>> packet
>>> then should be send the SACK for the DATA or not.
>>>
>>> Thanks,
>>> Salil
>>>
>>>
>>> -----Original Message-----
>>> From: Ashwani Kathuria [mailto:[email protected]]
>>> Sent: Thursday, October 15, 2009 12:58 PM
>>> To: Salil Agrawal
>>> Cc: [email protected]
>>> Subject: Re: [Sigtran] Abort chunk bundled with data chunk
>>>
>>> Hi Salil,
>>>
>>> When you are bundling anything (control chunk) with DATA chunk it
>>> should be placed before DATA chunks in the SCTP packets.
>>> Now if you bundle the ABORT chunk with DATA chunk in a single SCTP
>>> packet the ABORT chunk will be processed before DATA chunk and
>>> association will be broken down.
>>> So, that DATA chunk will have no significance as it's association is
>>> now broken by the ABORT chunk placed before it.
>>>
>>> --Ashwani Kathuria
>>>
>>> On Thu, Oct 15, 2009 at 12:37 PM, Salil Agrawal
>> <[email protected]>
>>> wrote:
>>>> Hi,
>>>>
>>>> We have a confusion while understanding the SCTP RFC4960 section  
>>>> 9.1
>>> it
>>>> says "DATA chunks MUST NOT be bundled with ABORT" so sender must  
>>>> not
>>>> bundle the data with abort.
>>>>
>>>> But the second paragraph states that "An endpoint MUST NOT respond
> to
>>>> any received packet that contains an ABORT chunk". Which means if
> any
>>>> packet is received at the receiver end where ABORT is bundled with
>> the
>>>> DATA it should not send any response. Does it mean that for the  
>>>> DATA
>>>> chunk SACK should not be generated? Please clarify.
>>>>
>>>> Thanks,
>>>> Salil Agrawal
>>>> _______________________________________________
>>>> Sigtran mailing list
>>>> [email protected]
>>>> https://www.ietf.org/mailman/listinfo/sigtran
>>>>
>>>
>>
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