[ewg] Re: [ofa-general] [PATCH 0/9] RDMAoE - RDMA over Ethernet

[Jason Gunthorpe]

On Tue, Jun 16, 2009 at 09:32:25AM -0700, Sean Hefty wrote:
> >RDMA over Ethernet (RDMAoE) allows running the IB transport protocol over
> >Ethernet, providing IB capabilities for Ethernet fabrics. The packets are
> >standard Ethernet frames with an Ethertype, an IB GRH,  unmodified IB transport
> >headers and payload. HCA RDMAoE ports are no different than regular IB ports
> >from the RDMA stack perspective.
> 
> I would refer to this as IBoE, not RDMAoE.

I disagree - this is very clearly not IB. Without interop at the SA,
CM and other management layers it is effectively a different protocol
- that only shares the same wire format for established QPs as IB.

Like FCoE the real challenge with something like this is all the
surrounding management and interop/interwork with the established base
(ie actual IB).

As Jim said, IBTA is going to be taking this up, and I'd be really
disappointed if the resulting specification was something that could
not interwork with IB at all layers.

> The RDMA stack should see these ports different than regular IB HCA ports.
> There are a lot of differences that should not simply be hidden or incorrectly
> assumed: QP0, QoS, multiple paths, routing(?), no SA, etc. 

.. Or it should actually do all this in some sane IB compatible way ..

Jason