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I have a small size business where we have around 22 PCs.

At present, I have the internet connected directly to a switch1 (We use dedicated leased line and I have been provided with 5 static IPs by my ISP).

From the switch I have connected a line directly to my asterisk server with a static IP provided by my ISP.

Then, from switch1 another line is connected to a router (Netgear WNDR3700v2).

In the router, I have configured one live IP and enabled DHCP with IP range between to

From the router, I have connected a line to another 24 port switch which distributes internet to all the PCs. We use Windows 7 Pro for all the PCs.

Now, I have taken another office in the opposite building where I will be running around 20 PCs. From Swtich1, I am connecting a line to a router (Netgear WNDR3700v2) in the new office.

In the new office router, I am configuring another live IP provided by my ISP and enabled DHCP with IP range between to

From the router, I am connecting a line to a switch and distributing internet in the new office.

I do not have any Microsoft server at moment.

How do I connect this 2 network together, so that we can share files, printers and NAS. I do not want to connect via wireless.

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1 Answer 1

The easiest thing is to connect your new router, to both switch1 and to your old router. In this way, all of your pcs will belong to the very same subnet, while the new router might very well route Internet traffic for the new pcs in the new building.

The connection should be established like this:

1.Enable DHCP on both routers, making sure the two ranges are separate. For instance, you might use for the DHCP range of the old router, and for the old router.

2.connect a cable from a LAN port of the old router to a LAN port on the new router.

3.connect a cable from switch1 to the WAN port of the old new router.

4.assign to the new router's LAN interface an address unused by either router, for instance

5.configure advanced routing in the new router, so that it has a new routing rule: all packets to the subnet (notice: 25, twentyfive, corresponding to netmask is to be routed through the equivalent thing on the old router, i.e., a new route for addresses (same netmask, through

The last rule makes sure that the addresses for the old LAN are correctly reached through the old router, and viceversa.

7.just to avoid doubts, make sure that all other netmasks, except for the two mentioned above, are, .e., /24, so that all of your pcs can talk to each other.

This way, you have a single subnet, correctly managed by the two routers in non-overlapping chunks, but you are tking full advange of your two external IPs, and of your ISP's capabilities, without overworking either router.

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