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Static Public and Private IP


Static Public and Private IP

I just moved from DSL where I had 1 static IP and had bridged the connection and configured DDWRT to port forward to all the junk I needed on my private network.  I have now switched to Uverse and need help figuring out the setup.


Here's what I have on my network:


Desktop A

Desktop B

Popcorn Hour (PCH)

Windows Home Server (WHS)


Junk I have laying around not in use but figured I would mention as options:

Linksys router

four switches

a box of network cards


Before the move to Uverse, I used the single static IP to lock remote machines I maintain to only be accessible from my static IP(among other security measures).  I also maintain a Windows Home Server in the house and Desktop A that I like to be able to access from the outside world.


I have a block of 5 statics with Uverse.  I would like for all my machines (Desktop A, Desktop B, PCH, and WHS) to have 192.168.1.x (private) static IP addresses.  I would also like to "point" one public static to Desktop A and one to WHS.  I'm not a network admin, but do know enough about tech to break junk, so please, somebody help me.


Basic idea:

Desktop A - public xx.xx.xx.241 - private

Desktop B - public xx.xx.xx.246 - private - same public as RG

PCH          - public xx.xx.xx.246 - private - same public as RG 

WHS         - public xx.xx.xx.242 - private 


I read a couple posts about multihoming network cards but I couldn't see to figure it out.



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Message 1 of 2

Re: Static Public and Private IP

k, there's a few things here:


  1. The RG does not support multihomed devices that share a single MAC address.  In other words, you cannot have a computer that has two IP addresses (one public and one private) on the same network card.  The only way to do that is if you use two network cards. 
  2. You may not need to use dual addresses on each machine.  If a machine with a private IP address and a machine with a public IP address need to talk to each other, the RG will properly route that between the two networks.  The disadvantage of that is the RG's 100 Mbps speed vice Gigabit, and the need to have Windows use some type of name resolution to find other computers on the network vice using Browser service broadcasts.
  3. If you were able to organize all services to work properly from a single static IP address on DSL, it should be possible to do the same thing with the RG, and you may not need to use your block of 5 static IPs at all.  The RG will get an IP address on its outside interface that never changes unless the RG is replaced -- you can forward ports on this IP address to go to various different internal hosts.

In your situation, I would stay with private IP addressing for all your computers, and open ports on the firewall of the RG to forward all the necessary traffic internally.  You would then also configure your work computers to allow incoming connections from your outside IP, and this would then give access to those work computers from all your computers with a single entry.


If we can set it up like this and get it working satisfactorily, you could even cancel the static IP addresses and save a little bit of money.


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