Subject: Re: Networking...
To: Allen Briggs <briggs@puma.macbsd.com>
From: Paul Goyette <paul@whooppee.com>
List: port-mac68k
Date: 08/25/1997 12:44:11
On Mon, 25 Aug 1997, Allen Briggs wrote:

	<video card stuff snipped>

> > I config'ed ae0, and *bam*, it locked up when I tried to ping another host.
> > IP: 10.1.1.5, netmask: 255.0.0.0, broadcast: 10.1.1.255.
> 
> Umm...  I've never used addresses in that range, but it looks to me like
> the broadcast and netmask parameters don't match.  I'd expect
> 
> 	IP: 10.1.1.5, netmask: 255.0.0.0, broadcast: 10.255.255.255
> 
> for a class A network or
> 
> 	IP: 10.1.1.5, netmask: 255.255.255.0, broadcast: 10.1.1.255
> 
> for a network with the broadcast address you specified.  If I understand
> the syntax right (probably not ;-), those two networks would be described
> as 10/8 or 10.1.1/24, respectively.

You got the syntax almost right.  In CIDR format, you almost always
specify the entire network address:  10.0.0.0/8 or 10.1.1.0/24

In any case, I definitely agree with you:  if the mask is 255.0.0.0, the
broadcast address shoould be 10.255.255.255;  if the mask is
255.255.255.0, the broadcast address should be 10.1.1.255

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