On Mon, May 26, 2014 at 3:13 AM, <thomas.mo...@orange.com> wrote: > 2014-05-22, Jesse Gross: >>> 2014-05-19, Jesse Gross: >>> - what about other link layers than ethernet that may have an ethertype >>> ? (thinking Infiniband at least for IP and ARP payloads, ATM too,...) >> >> These would presumably look more like raw Ethernet where we have a MAC >> header, then EtherType, etc. >> >> Tunnels are different because they are terminated before the main flow >> table. This means that anything extracted from the tunnel header is >> really metadata and not part of the payload flowing through the >> switch. > > You could also consider a generic design that does not make a special > case of tunnels, just considers them like a link layer among others, and > just like the current implementation preserves the Ethernet header, > preserves the tunnel header (or a part of it). You would still have some > metadata to carry; e.g. at least the incoming port identifier, and > eventually data from the part of the tunnel header that would not have > been preserved (e.g. outer header IP addresses).
Except that this information really is metadata because it is not part of the payload that is delivered to the switch - the tunnel is IP packets that are delivered to the host. At the very least, not stripping off some or all of the tunnel header is probably somewhat ambiguous with the tunnel packets that just happen to be passing through the switch. In any case, it is a moot point because doing this would break compatibility. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
