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What I have:

  • A linksys router WAG160N with firmware version 2
  • A "pool" of 5 external static IP's provided by my ISP
    • All the required configuration values for the static IPs such as (Subnet Mask, Gateway and static DNS 1, 2, 3)

Current WAN Configuration:

  • Encapsulation: RFC 2364 PPPoA
  • Multiplexing: VC
  • QoS type: UBR
  • DSL modulation: MultiMode

What's connected to the network:

  • 1 x Server (That I want to make available to the outside)
  • 5 x Desktops with static internal IP's, such as 192.168.0.xx
  • 2 x Network printers, also with internal static IP's
  • 2 x Laptops
  • 1 x NAS (Network Attached Storage) also on static IP

What I want to do:

I would like to make the server available from outside the network, for example from your house. The problem is that Im not really sure how to do this. I have tried following the steps on the instruction manual in Linksys but they do not seem to work, once I set it up as shown bellow, I loose internet and all hell breaks loose.

Going into further detail, I would prefer if the network is changed as little as possible, by this I mean that all the computers stay networked within eachother and only the server is accessible from the outside the network.

What I need HELP with:

I have read around that it is possible to set a 1-1 NAT (I know where it is in the menu but have no clue what it does...) so that I can NAT a single public IP directly to a single private IP (in our case the server). But please, How do I do that? Or maybe an alternative?

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1:1 NAT Maps a single public IP to a single Private IP instead of the standard public IP to multiple private IPs. This way you can have a server accessible both publicly and privately as well as have it still behind a firewall. This requires that you have multiple public IPs, one for the 1:1 NAT and one for the standard NAT. – MaQleod Mar 17 '11 at 15:46
up vote 1 down vote accepted

I do not know how to set up 1-1 NAT on your type of router or if it even supports having multiple IP's

But here is the way I do it (basicly using NAT-loopback instead of 1-1 NAT

I have (same as you) 5 IP's and everything hookedup to a Zyxel Zywall USG 100 (professional router/firewall) After that I have: - 5-6 private computers (in the private zone) - 2 physical servers (in the server zone) - 9 virtual servers (in the server zone)

1 IP is set for my router to use as gateway (so all outgoing connections are running trough here)

But for incoming traffic I use NAT loopback routing with protocol: ANY this means for my settings: - original: - mapped: - Port mapping: ANY

This I have set-up for my mail server, since it uses a lot of different ports and basicly just has enough importance. So when you connect with on any port it will go to my mailserver and since nat-loopback is enabled, it also responds on the same incoming IP

But my router also allows me to override by making a more specific setting for example for acces to my remote desktop server... So in this setting I do tell that port 3389 will go to a different server...

This is usefull because instead of dedicating an entire IP to one server, You can still use the IP for a different server...

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