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Re: [vox-tech] dsl ideas
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Re: [vox-tech] dsl ideas

----- Original Message -----
From: <jdnewmil@dcn.davis.ca.us>
To: <vox-tech@franz.mother.com>
Sent: Sunday, December 03, 2000 11:52 PM
Subject: Re: [vox-tech] dsl ideas

> On Sun, 3 Dec 2000, Jay wrote:
> > I thought the idea behind 5 ips is:
> This is "an" idea... one of many possible...
> >
> > 1 ip firewall/NAT/Router/Gateway (3 NICs, 1 for external, 1 for your
internal, 1
> > for your DMZ
> >
> > DMZ
> Not sure what you mean by lumping "DMZ" with individual ip numbers... a
> DMZ is a network... a group of ip numbers.
> > 2 ips DNS

I mixed my metaphors, I was talking about the NICs on the firewall, 1 for
internet, 1 for DMZ, 1 for your internal network.  1 ip for your firewall to
communicate to the external world, the other 4 are the DMZ (which communicate
thru the firewall).

> Seems better to arrange for someone else to handle your backup DNS

I suppose, but don't you have to pay for that then?

> > 2 - pop/imap, HTTP, SMPT, and whatever else external services
> 5 ips arises because a 29 bit netmask leaves 3 bits for your network,
> which would be 8 addresses except that the network and broadcast addresses
> are usually reserved, and the isp needs to keep an address to configure
> the upstream router with.  This is about the smallest practical network
> size.

Makes sense.  Why isn't the netmask 36 bits?  Isn't it 4 bytes long?  How do I
figure out what the range of IPs I have if I know my netmask and I know the
first IP.

i.e. if I'm using netmask of and my IP =

> ---------------------------------------------------------------------------
> Jeff Newmiller                        The     .....       .....  Go Live...
> DCN:<jdnewmil@dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live Go...
> Work:<JeffN@endecon.com>              Live:   OO#.. Dead: OO#..  Playing
> Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
> /Software/Embedded Controllers)               .OO#.       .OO#.  rocks...2k
> ---------------------------------------------------------------------------

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