Sharing Internet in LAN over USB Mobile Internet Stick (Windows 7)

Recently I had to configure a network of 8 computers (running Windows 7)
and provide internet access to all of them through an USB mobile internet stick
connected to one computer (let’s call it the Gateway computer ).

However, since all of the computers were connected only to a wired Gigabit LAN switch at first ,
and no DHCP server was present, I ran into some issues. A static IP configuration in Windows did not provide internet access, although the computers could still communicate to each other over LAN.

What you will need in order to set this up:

- Bridge or Router in bridge mode ( Thomson ST780 in this example )

- Mobile Internet USB stick ( Vodafone Mobile Connect in this example )

- Gateway computer ( the main computer with your USB internet stick plugged in)

- Ethernet Switch connected to all the computers and the Router/Bridge

Note: You can also manage this by using a wireless network with wireless network adapters attached or bulit in to each computer.

We can create a Shared Internet Connection over LAN following these main three steps:

Step 1: Configure the Gateway computer
Step 2: Configure the Router/Bridge
Step 3: Configure all other computers on the network

Step 1: Configure the Gateway computer

Set the “Obtain IP Address automatically” option on your IPv4 settings of the Ethernet adapter (Local Area Connection Properties).

Set up internet connection sharing by opening the properties of your Internet network adapter ( i.e. VMC USB stick ). After this is done, check your LAN IPv4 settings – they should indicate that the address has been set to 192.168.137.1 with subnet mask of 255.255.255.0 . This is mandatory!

Step 2: Configure the Router/Bridge

This is the required router/bridge configuration:

DHCP pool: 192.168.137.2 – 192.168.137.253
DNS servers: 8.8.8.8 and 8.8.4.4 (Google public DNS)
Server: 192.168.137.254 (the Router/Bridge ETH IP Address)
Default Gateway: 192.168.137.1 (the static ETH IP of the Gateway computer with USB internet stick)

Be sure to remove the default DHCP pool (i.e.192.168.1.0/24…) by editing the configuration file. If using Thomson ST780, first you have to download the current configuration, modify the .ini file in a text editor and save as a new config file (i.e. new.ini) which you will then upload back to the router. The router will reconfigure itself to your given specification (presuming no errors were present).

Step 3: Configure all other computers on the network

Note: If you’re not logged in as Administrator, do so before you start,
or elevate the actions when prompted.

The only thing you need to set for all other computers is to have automatic IP address assignment.

1) Open the Network and sharing center ( press Start and type “Network and sharing center” )

2) Find your network in the “View active networks” sections and click the “Local area Connection” Link ( following the “Connections:” label )
Note: The name “Local Area Connection” may vary on your system.

3) On the “Local Area Connection Status” window, click the “Properties” button

4) Select “Internet Protocol Version 4 (TCP/IPv4)” and click the “Properties” button below the list
Note: You can do the same for IPv6 once done with step (6)

5) Check the radio button called “Obtain an IP address automatically“.
You can also check the radio button called “Obtain DNS server address automatically

6) Press “Ok” to save and close the configuration

7) Press “Ok” on the “Local Area Connection Properties” window

8) Close the “Local Area Connection Status” window

That’s it!
You’re local network should now be able to access the internet over a shared internet connection!

 

 

Network Tweaks, Tutorials | Posted on September 10, 2013 by .

About Kristijan Burnik

Kristijan Burnik is a Programmer and Web Developer specializing in Server-side and Client-side Technologies and Application Development on Linux Servers and Windows Desktop . Also has experience in Networking, Desktop application development as well as Android mobile application development . Experienced in Programming Languages like Java, C, C++, C#, PHP, Javascript, MySQL and somewhat in other languages like Bash, Perl & Python. Sometimes he works as a Graphical Designer for digital production as well as for printing and advertising. He dedicates his spare time writing Tech Articles on his blog in order to share his work with others, as well as to document his projects for his own use. He's also an Educator & Mentor in field of Algorithms and Programming to young programmers in Zagreb, Croatia.