Re: [Ips] [iSCSI] iSER on InfiniBand

Eliminating the TCP dependencies in iSER would be a good idea.

Once a connection between two RDMA Endpoints is established,
iSER can be defined as a series of RDMA Messages.  As such
they are dependent only on RDMAP, and not on the underlying
LLP. Adapting to other IP based transports would be easy,
such as SCTP, and should be supported.  It also enables
non-IP transports, which is something that I do not believe
anyone would object to, especially if a clarifying draft
establishes how to do iSER over generic RDMA services
without having to specify the mapping of generic RDMA
services to any specific non-IP transport.

The only missing service required is support of an initial
message before endpoints are selected (the equivalent of the
MPA Request and Reply messages and their private data).

The key requirement is specifying that the private data
contain enough information to enable RDMA endpoints to
be selected.  After that remaining iSCSI negotiations
can be completed using Send messages.

Private data exchange prior to pairing RDMA endpoints
is already supported for both MPA/TCP and SCTP.  The
essential similarity is already documented in the RDDP
applicability draft.

If a "non-streaming mode" method of establishing an
iSCSI connection is defined that is compatible with
the existing private data exchange followed by Send
messages for the remaining negotiations it will enable
other IP transports, such as SCTP, and do so in a manner
that is fully compatible with existing RDMA APIs such
as DAPL and IT-API.

It would also make it easy to port "non-TCP-dependent"
iSER to non-IP transports, should anyone wish to do
that outside the scope of the IETF.

Eliminating iSERs dependency on a single RDMA transport
is something that should be done anyway.  The fact that
doing so would be useful for InfiniBand ports is certainly
not a reason to avoid doing something that should have
been done in the first place.

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