Michael R asked:
I have a simple LAN. All workgroup PCs. Network Attached Printers. No domain controller. Cable internet access, router. How would I extend this LAN over T1 and have computers on the otherside act like they were on the same LAN? Would they all talk to the DHCP on the router? Some companies who would install the PtP show routers on each end such as a NetVanta 3430, but would any special considerations be needed as far as regular network connectivity between computers on either end of the PtP?
For clarity, I do not want to connect the two places by VPN over the internet. The reasons are: The second location does not have any good internet access available. No DSL, no Cable. I would have the second location get it’s internet access from the Cable at the first location. The two will be linked by a Point to Point T1.
I’m not interested in a wireless solution, I don’t want anything that is affected by weather. I also can’t run a fiber optic cable 15 miles through the country and city between the locations. Point to Point T1.
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Study about Virtual Private Networks (VPNs) over the Internet. It’s a complex technology if you want to master it. You also need two hosts directly (with public addresses,no NAT) to act like the two ends tunnels of the VPN.
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If it’s not a very big geographical distance between the two locations, try an optic fiber or radio connection. (I recommend FDDI since it’s safer and more reliable). For this you need either two access points (Wireless) either two Ethernet to Fiber media convertors.
take another switch and connect the uplink port to the existing switch .. and in that new switch LAN port connect you workgroups .. it will work .
As I see it you have a CATV Internet access at one location with a router. Let’s assume this router has assigned LAN IP addresses in the 192.168.1.0/24 subnet (all IP addresses are 192.168.1.x (x from 1 – 255); subnet mask 255.255.255.0; default gateway and router address 192.168.1.1.
You have a second location, called location 2. You wish to install a point – point T1.
Point – point T 1 lines are terminated with a smart jack. You will need a router at each location that has a csu / dsu built in. The Adtran Netvanta 3200 series routers will do this job nicely. The Netvanta 3430 may be larger than you need but if you wish to replace the CATV modem, this may be proper. Make sure you procure the proper NIM interfaces for the Netvanta routers; you will need a T1/FT1 NIM for the point – pont interfaces.
At Location # 1, the LAN has the 192.168.1.0/24 subnet as mentioned above. Give the Netvanta 3200 at this location static IP 192.168.1.2, do not provide IP via DHCP from this router as the cable modem’s router is assigning DHCP here already, and plug its LAN port into the network switch. Give this Netvanta 3200 a WAN IP of 10.10.10.1. subnet 255.255.255.0, default 10.10.10.1
At Location # 2. The WAN IP is 10.10.10.2, subnet 255.255.255.1, default 10.10.10.1. Turn on LAN DHCP; assign this router’s LAN IP at 192.168.2.1 with 255.255.255.0 subnet (the subnet at location 2 is 192.168.2.0/24).
Now you need to set up static routing tables in both Netvantas so the Netvantas will route from 192.168.1.0/24 subnet to and from 192.168.2.0/24 subnet. Static routes are best because it is very small. You need not activate RIP or BGP or any other automated protocol.
Computers on both ends of the Point – Point obtain their IP addresses from their respective DHCP server on their own subnet.
Make sure to restrict the DHCP range so static LAN IP addresses cannot also be assigned by the DHCP server.
This should do it.
You may also wish to put in a point – internet at Location 2, get Static IP addresses from your ISP, put in Adtran Netvanta 2100 routers and install a VPN between the 2 locations. Location 1 would use 192.168.1.0/24; location 2 would use 192.168.2.0/24. This may be easier and less costly and achieve the same.
Well, in direct answer to your question – you would have to bridge them. Yes, you need a router on each side to terminate the T1 on, and then you need to set up bridging across the serial circuit – DHCP would come from the same server and everything. I would never recommend anyone do this – bridging across a T1 is not a wise move.
Instead, I would recommend that you route across the T1 and set up the office as it’s own LAN. DHCP could be served locally off of the router, or they can come across the Point-to-point and get DHCP from there (if that happens, you need a way to turn the broadcast into a unicast to get it across the serial interface – “ip helper” in Cisco routers does this). You could either run static routes (at the remote site – a default static is fine) and if you NAT outbound to the Internet you may need to ammend you NAT configuration – but for the most part this is pretty easy.