André Wienck skrev:
> Salut,
> 
> On Fri, 20 Jul 2007 11:12:51 +0200, Johnny Billquist
> <bqt@softjar.se> wrote:
>>> - only allow it to broadcast packets to all interfaces.
>> That would actually be rather nice. I didn't think of that one, but it 
>> would actually perhaps make the most sense.
>>
>> Why wouldn't the first one be what I want?
> 
> As outlined earlier, you get into tons of trouble then. What about
> blatantly broadcasting out the pppoe0 interface? Or what about the
> situation where you have a number of NICs connected to the same network
> interface for some reason? You might get confused.

I don't believe point-to-point interfaces should be selected if just 
interface were sent on. But if all were, then I fail to see the problem. 
Programmers that write bad programs might get confused, but they are 
already confused so that wouldn't be any different.
For the rest, it would just mean that the broadcast behaved in what I'd 
say were the most proper way.

Arguments like "confused" are just nonsense. There is absolutely nothing 
technically wrong with sending a broadcast message to several 
interfaces, neither is there any problem with getting duplicates in case 
they happened to be connected to the same segment.

> Also, I would hardly see any use of broadcasting out all interfaces.

Really? I can see uses for it. Just as I can see uses for broadcasts in 
general. If you want to send something to everyone you are "connected" 
to, that's the way you'd want to do it.

I could even give you one example of a daemon that I'd definitely use it 
on, and that's rwhod. And I'm not even trying to think up something 
here. It's just so obvious that there are times when it would be useful.

> Most of the time, broadcast to 255.255.255.255 is used for some
> configuration purposes, and thus directed out a specific interface
> (using the bpf interface). For most other stuff that communicates to
> many hosts on many sides, you would rather use some type of broadcast.

255.255.255.255 *is* a type of broadcast. And if you want to send 
something to all interfaces, which you sometimes do, then it would be 
ideal. And no, I don't agree that 255.255.255.255 mostly is for 
configuration.

> Also, we should remember what the rest of the world does in these
> situation.
> 
> I think not even Windows screams out on all interfaces...

No. Windows have a routing entry for it, so you pick which interface it 
should go to.

	Johnny


-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt@softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol