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One Printer, two LANs.

I have  LAN1 of 5 computers all with static external IPs assigned by our ISP that connect to a Netopia router. The Netopia connects to our ISP. I have LAN2 with 4 wireless computers that use dynamic local IPs assigned by a Linksys router. The Linksys has a WAN address assigned by the Netopia so that it can act as a gateway to the web for the wireless computers.

There is one printer attached to a computer on LAN1 via USB and shared across LAN1. How can the computers on LAN2 access the printer?
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Please give an example of an IP address on LAN1.  It doesn't sound quite right and this will clear things up.  That is, is the address public or private?
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LAN1 uses public IPs such as 74.165.38.102 through 106.
So, you have printers on computers with public IP addresses.  Seems like I could print to them from here.   So, one should be able to print to them from the other LAN in the same manner.  At least I think that makes sense....

But, of course, the reverse wouldn't be the case unless you *at least* had port forwarding set up on the Linksys router.

In the paper I attached, there are a number of ports that have to be open to accommodate file and print sharing.  I've only been concerned about file sharing so I don't know for sure which firewall settings might be NOT needed for only printer sharing or if there are additional ones needed for printer sharing.
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fmarshall: Where is the attachment?

Is it possible to get out to the web, and back into the network using the same netopia router going both ways?
I assume the following:

If you can get to the internet from the private LAN then you can get to your own public addresses.

Now, if the Netopia router is providing some kind of firewalling services then this may not be entirely the case.

Getting back to the LAN should be no different than any web page responding.  But, again, this may be limited in some ways.

Here is the attachment I referred to ...
Windows-7-File-and-Printer-Shari.pdf
This leads me to a question:

What is the Netopia doing for you?

I can imagine a couple of cases:
- the Netopia simply connects you to the ISP.  In these cases I've seen it done this way:
The router has a WAN address that is part of an ISP subnet that has an ISP gateway on the other end of the link.
The router has a LAN address this is part of your assigned public address block - usually a subnet - and the router becomes the gateway for all of your other public addressed devices.
In this case I usually plug the router LAN into a switch that I refer to as the "Internet Switch".  There is no firewall involved here.

In another case:
- you want to have a firewall that intercedes between your devices with public addresses and the unfiltered internet.  A similar arrangement as above may apply but with firewall features turned on in the router.  Then you might refer to the "space" on the switch as a DMZ.
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The Netopia, as stated, connects us to our ISP. It also offers some protection. For instance I could not use VNC to access the computers with public IPs until I opened the appropriate ports on the Netopia. So I assume that I will have to glean the port info from the document you sent, and apply it to the netopia and ZoneAlarm. (Zone Alarm is running as a firewall on the computer with the attached printer.) By the way, the computer is running WinXP Pro.
With XP Pro I've not run into the port / address subnet scope issue at all - just turn on File and Printer sharing as usual / which is likely already the default.  This only came up with Win 7.
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fmarshall - you said "... just turn on File and Printer sharing as usual..."

Of course File and Printer Sharing is already on in order to share the printer on LAN1 as stated in the opening message. I am a bit confused by your statement, since the idea you put forth was to print via the web. I don't see how your latest comment contributes to that end. Please elaborate.
I was referring to the firewall settings necessary for inter-subnet file and print sharing.
For Windows XP it appears there is nothing to do.  
For Windows 7, there is.
That's my experience with both.

Yes, it appears that the Netopia settings would have to be adjusted in view of what you've described.

Maybe do an experiment with the Netopia out of the picture for the computer with the printer?
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I ran out of time on this project and scrapped the public IPs. Everything now runs on local IPs.

Thanks fmarshall for trying to help.