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From: dfc@hpindda.HP.COM (Don Coolidge)
Newsgroups: comp.sys.hp
Subject: Re: Inquiry about broadcasting an address on a HP9000/320 (6.2 HP-UX)
Message-ID: <4310075@hpindda.HP.COM>
Date: 29 Nov 89 23:49:58 GMT
References: <1070@mit-amt.MEDIA.MIT.EDU>
Organization: HP Information Networks, Cupertino, CA
Lines: 26

If you're asking if HP-UX provides a way to arbitrarily configure your
interface IP broadcast address (a la 4.3BSD), the answer is, "not yet".
That capability will be available as a patch to the 7.0 HP-UX release,
and will be an integral part of all subsequent releases. 

The interface broadcast address is currently defaulted to all ones (4.3-ish,
and conforming to the Internet Hosts Requirements Document), subject to the
interface netmask and IP address. In your case (netmask 255.255.0.0; IP address
18.85.0.30), that would result in 18.85.255.255 (as in your example).

If other nodes on the LAN are seeing something else, you have a problem
that I don't understand and that should never be able to happen. If that's 
the case, please contact me via email at :

	dfc@hpindaw.hp.com

There's only one way I can conceive of that other nodes on your LAN could
be seeing 18.0.0.0 - if you have an application using sendto() with 18.0.0.0
specified as the target IP address.

By the way, even though the interface broadcast address is defaulted to all
ones, HP-UX will also recognize inbound and outbound datagrams with all zeroes
as valid broadcast packets.


- Don Coolidge