From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Eric W. Biederman" <ebiederm@xmission.com>
Subject: Re: [PATCH V2 09/12] net/eipoib: Add main driver functionality
Date: Sat, 04 Aug 2012 16:19:03 -0700
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Or Gerlitz <or.gerlitz@gmail.com> wrote:

>On Sun, Aug 5, 2012 at 12:23 AM, Or Gerlitz <or.gerlitz@gmail.com>
>wrote:
>
>> The idea in eIPoIB was to allow IP apps running on VMs under a
>Para-Virtual set of
>> mind, e.g when the Linux PV networking stack comes into play, to use
>that stack w.o > modifying it. When looking on that, we thought so far
>so good, and went in the way
>> posted here. If reusing your last sentence... this driver provides a
>way for apps to use
>> the PV stack AND IB whilst using something familiar, like IPv4.
>
>OK, when I said the PV stack, I meant the portion of the PV stack
>which assumes Ethernet link layer, ofcourse... If someone uses routing
>they don't need this driver.
>
>Again, since the app only uses IP,  which is well defined, etc. the
>work done by the eipoib driver, didn't seem as hackish messing, so I'm
>again with that WW (Why/What) question from 5m ago.


Something is missing from your sentence. 

What is the alternative that you view as worse?

Juast as a point of information.  In general when bridging is desired but not possible people deploy proxy arp.

I completely fail to see how having the VM output to a tun interface and then routing that, would not be supported by current solutions.  I believe that is where VM solutions all started networking wise.  Outputting to an interface is needed to support interfaces like 802.11 where bridging frequently does not work.

Eric