How to connect 3 LANs with 3 Linksys Routers

[Fargowind]

Hi,
I've been trying to figure this out for a while with no success but really would like to get it to work.
I have three separate networks:
192.168.1.0
192.168.1.5
and soon 192.168.1.10
I have a 2Wire DSL modem with 4 LAN ports,
a Linksys WRT54G
and a Linksys BEFSR41.
The 3 networks will be in 3 different locations (a field office, a plant and a tunnel....yes...). All these locations will be connected to the field office through DSL modems. all the workstations will be running Win XP Home or Pro.
Here is my question: how do I setup my Linksys routers to talk to one another so that I can access files on any computer on any of the three LANs from the field office but allow only a few selected computers on the Plant or Tunnel LANs to access the computers in the field office?
Your help is most appreciated.
Thanks

 

[bcastner]

You need some more equipment.

. You need an endpoint router that can support at least two VPN tunnels.

. You need two endpoint routers that can support at least one VPN tunnel

. You need to subnet your LAN differently (192.168.1.0, 192.168.2.0, 192.168.3.0)

Create the VPN tunnels between Field Office and Plant, and Field Office and Tunnel.

 

[Fargowind]

Thanks for your reply bcastner.
What routers do you suggest I should look at, as I've tried to establish a VPN connection with my WRT54G with no success (IPSec PPTP and right ports enabled + tried using different firwares etc...).
Also would I need any additional software or would the embeded WinXP Pro VPN software be good enough?
I heard of routing also do you think I could manualy set routing tables in my linksys routers or would that not work for me?
Thanks

 

[bcastner]

Upgrade the firmware on the WRT54G. The Sveasoft and the newest Linksys firmware both fix PPTP issues.

The XP VPN client software should be sufficient for a single connection.