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Date: Wed, 6 Jul 2005 09:54:48 +0100
From: David Malone <dwmalone@maths.tcd.ie>
To: snort Snort <snort_sam@yahoo.com>
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Cc: stable@freebsd.org, freebsd-current@freebsd.org
Subject: Re: network resquest to tap pseudo device driver
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On Tue, Jul 05, 2005 at 10:48:55PM -0700, snort Snort wrote:
> Can anybody tell me what benefit for building a tap
> pseudo ethernet device driver for some sort of network
> communication? Why not directly communicate thru a
> "real" ethernet device driver like fxp0, xl0, etc.

A tap interface can be used by machine that don't have real hardware
(for example, a vmware virtual machine) to access a real network.
Another possibility is to use a tap interface to bridge two ethernets
together over an intermediate IP network, possibly encrypting the
frames in transit.

	David.