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Date: Tue, 21 Oct 2003 13:21:42 +0100
From: Bruce M Simpson <bms@spc.org>
To: Barney Wolff <barney@databus.com>
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cc: julian@elischer.org
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cc: sarat chandra Annadata <saratchandra_a@yahoo.com>
cc: freebsd-net@freebsd.org
Subject: Re: Help Broadcasting a UDP packet on the LAN:URGENT
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On Mon, Oct 20, 2003 at 08:42:50PM -0400, Barney Wolff wrote:
> And of course any application that actually needs to send such a packet
> on every interface can loop through the interfaces, using the technique
> on each one, getting the reply, removing the 255.0.0.0/8 alias, and
> moving on to the next interface.  If it were up to me (as of course it
> is not) I'd leave it at that and not clutter up the kernel.

I would take the view that applications shouldn't mess with the routing
table if they don't have to, particularly if the application in question
is a routing daemon...

The IP_ONESBCAST socket option doesn't create any clutter; it coexists
comfortably with delayed/hardware checksumming and adds virtually no extra
latency to the output path. In any event, the idea was borrowed from BSD/OS,
and seems to work well there.

BMS