[Courses] [Security] Firewalls: Ipchains syntax and implementation

[Kai MacTane]

At 4/9/02 10:18 PM , Raven, corporate courtesan wrote:

> > I admit I'm used to the Windows world. We never had problems with NT
> > Workstations losing their leases if the machines were on -- they renew
> > automatically.
>
>         With Linux, some dhcp clients do and some don't, I think.  I'm
>not terribly experienced with this one, since the only *nix workstations
>tended to be the admin boxes with static IPs.

I must admit, this is the boat I'm in, too. IME, *nix boxes have always had 
static IPs. Of course, I know that this isn't universal -- lots of people 
have connected Linux boxes to their old-style ISP using PPP -- it's just 
that I've personally never run into a dynamic-IPed *nix box.

>         Does the above make sense to you?  If not, please say so, and
>I'll try to explain a different way.  Subnet masks are one of the most
>confusing concepts in networking; mastering them is really something to
>be proud of.

If you find the thing I wrote to Malcolm on TechTalk to be useful, feel 
free to forward it over here. I think there may be an even clearer way to 
have described stuff, but I think I did a decent job, at least. (My writeup 
essentially explains CIDR notation, and assumes you're used to 255.0.0.0, 
255.255.0.0 and 255.255.255.0 as subnet masks for Class A, B and C networks 
(and know what Class A/B/C is about), but doesn't really assume much (if 
any) more.)

                                                 --Kai MacTane
----------------------------------------------------------------------
"Before you slip into unconsciousness,
  I'd like to have another kiss,
  Another flashing chance at bliss..."
                                                 --The Doors,
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