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

[Woodruff, Robert J]

Eli Cohen 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.

This seems like a hack to try and shoehorn this in under the IB portion of
the stack. It makes more sense for it to be it's own transport type,
a peer to IB and iWarp. 

>IB subnet management and SA services are not required for RDMAoE operation;
>Ethernet management practices are used instead. In Ethernet, nodes are commonly
>referred to by applications by means of an IP address. RDMAoE treats IP
>addresses that were assigned to the corresponding Ethernet port as GIDs, and
>makes use of the IP stack to bind a destination address to the corresponding
>netdevice (just as the CMA does today for IB and iWARP) and to obtain its L2
>MAC addresses.

Since it does not require SM or SA services, then this is another reason
to make it it's own transport type rather than try to fit in under the IB
core services and then emulate the expected behaviour that the core mid-layer 
and ULPs expect for things like SA queries.