Subject: Re: [rddp] MPA issue (3): Rejected Connection bit - Rough Consensus

From: "Talpey, Thomas" <[email-masked]>
Date: Thu, 15 Apr 2004 07:06:37 -0700

At 01:31 AM 4/15/2004, Caitlin Bestler wrote:
>However, I believe it has also been shown that the option to return
>the TCP connection to the ULP is mostly a theoretical nicety. There
>is no identified *need* for such a feature. So if anyone put forward
>a scenario where it was difficult to return the TCP connection then
>it would probably be agreed to allow the MPA layer to simply
>terminate the connection after the Reset bit.

The NFS/RDMA mode of the NFSv4/Session protocol supports a mode
where RDMA mode is offered by the client via NFS/TCP exchange, but
may be declined by the server (for example, inability to support 
requested RDMA parameters). Currently, this exchange is handled
in TCP mode, but we are examining options which may lead us to
also perform it via MPA, using private data and reject. In this case,
leaving the session in TCP mode will enhance availability and
robustness.

While we have no current implementation with this requirement, i.e.
we have no proof it is compelling, it is trivially easy for the RDMA
provider. Therefore I argue for inclusion of the requirement that the
MPA layer return to idle mode.

Tom.