Re: [Re:] comment clause 5

On Feb 11, 2004, at 2:15 PM, Shah, Hemal wrote:

>
> Is:
> If an LLP does not support teardown of a LLP stream independent
>        of other LLP streams and a DDP error occurs on a specific DDP
>        Stream, then the LLP MUST label the associated LLP stream as an
>        erroneous LLP stream and MUST NOT allow any further data
>        transfer on that LLP stream after DDP requests the associated
>        DDP Stream to be torn down.
>  
> Suggest:
>  
> Add a definition for erroneous LLP stream in clause 4.2
>  
> "LLP Erroneous Stream - The LLP layer may mark a stream as being
> erroneous to indicate to the DDP layer that the stream may no longer be
> used for transmission of DDP segments."
>  
> [hvs] Change is not accepted. The text clearly says what LLP must do
> when the stream is marked errorneous.

I definitely concur with not making the change. It is a very
reasonable for an SCTP implementation to be layered, and for
the SCTP layer to have no concept as to which SCTP streams
are in what state. The SCTP adaptation layer knows that,
but would only check that state on inbound packets, trusting
the DDP layer not to send DDP Segments on a dead stream.

This is more of an issue with the SCTP adaptation because
the stream going dead does not necessarily close the SCTP
association, or block the SCTP Stream from being re-used
for a different DDP Stream (anymore than closing a TCP
connection permanently forbids the same source/destination
from ever being re-used).