[Bridge] Re: Small packets

Andy Gospodarek andy at greyhouse.net
Mon Oct 29 08:06:21 PDT 2007


On 10/29/07, Benny Amorsen <benny+usenet at amorsen.dk> wrote:
> >>>>> "LS" == Leigh Sharpe <lsharpe at pacificwireless.com.au> writes:
>
> LS> Standard e1000 hardware. The packets being bridged contain a VLAN
> LS> tag, which is included in the 60 bytes.
>
> The e1000 has VLAN acceleration. The VLAN tag is sent in a separate
> register. If you do packet capture on the sender, the packet will
> likely look 60 bytes long, even if it is 64 bytes on the wire.
>
> The same thing happens on receive. Packet dumping with VLAN's is a bit
> of a mess in Linux. If you're lucky you can find a card without VLAN
> acceleration to do the packet dump.
>
>
> /Benny
>

Are these the lengths on the wire or when captured on the host?   The
smallest VLAN tagged frame should be 68 bytes IIRC.  A tagged frame
that is 64 bytes seems too small.


More information about the Bridge mailing list