two NICs -- channel bonding -- tradeoff

[Kragen Sitaker]

Someone asked:
> I wonder if anyone know if the "out of band" feature of TCP/IP (or is
> it UDP/IP?) actually gives priority to packets at the network device
> queue, or if it simply provides a seperate buffer for the socket?  One
> idea would be for the kernel to automatically route "out of band" data
> via a different device.

The "out of band" feature is a feature of the BSD socket interface.  On
TCP it translates into "urgent data", which is just data in the normal
data stream with an 'urgent pointer' pointing to it.

Accordingly, 'out of band' data cannot usefully be routed through a
different device, because it will not be received until all previous
packets on the same TCP connection are received.

You could use a different TCP connection (with different IP QoS flags)
though.

-- 
<kragen@pobox.com>       Kragen Sitaker     <http://www.pobox.com/~kragen/>
TurboLinux is outselling NT in Japan's retail software market 10 to 1,
so I hear. 
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