Re: [Announce] rxe dev tree available (soft RDMAoE)

Roland Dreier
2009-12-17T23:46:46Z

> The ICRC isn't even necessary from a technical sense for DCE. The
> underlying reasons for the ICRC/VCRC split are not really present for
> ethernet. Considering RDMAoE isn't interoperable with existing IB anyhow
> and DCE can't do routing, the best course would be to just get rid of
> it entirely.

Not sure I agree... it would be entirely possible and sensible to create
an IBoE router (and if the IBoE GRH used global scope addresses, pretty
much the same as routing IPv6), and I think you would want end-to-end
ICRC protection in that case (since the router would be regenerating the
ethernet CRC). Even in the ethernet case there are probably realistic
cases of adding a VLAN tag or something that require the CRC to be
recalculated by a switch -- and some switches probably cut corners and
just recalculate the CRC of all packets on egress, just to avoid
conditional cases.

- R.