[VLAN] vlan Q in Q - [WAS Re: Using a switch fabric to emulate multiple NICs]

[ajz at cambridgebroadband.com (Alex Zeffertt)]

O
> > 
> > I'd appreciate any comments regarding how this should be done properly.
> 
>  From a brief glance at the code, I bet that a program opening a raw socket and passing
> a pre-constructed VLAN packet to the VLAN device will cause double encapsulation, which
> is not what I would want to happen.  If we do not add the additional 4 byte header when
> the VIDs are the same, I believe that would fix that problem.  It would create a small
> problem for your device in that the users could not use the VLANs that your
> box uses internally.
> 


Thanks for having a look Ben.

I think I am missing something though.  Why would a program ever want to pass a "pre-constructed
VLAN packet" to the VLAN device.  I assumed that the whole idea was to make vlan devices look like
traditional ethernet devices to the rest of the kernel.

Alex