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Date: Wed, 6 Jul 2005 13:21:50 +0100
From: Bruce M Simpson <bms@spc.org>
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.

Sometimes you want to emulate Ethernet over another link layer.
Or you might want to just simulate an Ethernet network.
Or the Ethernet hardware might not actually physically exist.
Look at OpenVPN and VMware for concrete examples of the use of tun/tap.

BMS