basic server question

[Kurt Granroth]

On Sunday 02 September 2001 05:10 pm, Eric wrote:
> Given the following configuration, how many static IP addresses will I
> need? I have one static; is there a mechanism (NAT?) whereby I can set up
> the following network with only one static IP?
>
> I have a cisco 675 DSL router, which goes to a zonealarm firewall until i
> get the knowledge to configure linux box as a firewall, and the cajones to
> trust my data with it.
>
> Whichever firewall is used, I want host my own site on Apache Web Server,
> and also host some type of e-mail server.  Lastly, I would like to set up
> an SSH server, and create a VPN between home and work.
>
> Is one IP address sufficient for this, or do I need to pay qworst even more
> money?  Could you explain?  Thanks very much,

In general, you need one static IP for every physical line you have to the 
"outside" world.  So if you have a standard single DSL line coming in, then 
you only *need* one address.

Basically, all computers in your LAN will have a private IP address (10.x or 
192.168.x) and only one will have the "real" address.  The one with the real 
address is your firewall.  It needs to be configured to masquerade all the 
internal hosts so that they can access the 'net *and* to (possibly) route all 
web/mail/ftp services to the correct internal hosts.
-- 
Kurt Granroth            | http://www.granroth.org
KDE Developer/Evangelist | SuSE Labs Open Source Developer
granroth@kde.org         | granroth@suse.com
            KDE -- Conquer Your Desktop