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Internet connection Sharing

Setting up a LAN and sharing your Internet Connecton
2003-03-28 (updated: 2009-11-01) by
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There are a couple of different ways to share your Cable Modem or xDSL connection over multiple PCs. Your ISP provides you with one or more IP addresses (or simply IPs) used to identify your PC. Most providers will assign just one IP per residential account, which means that for the outside world, the Internet in this case, you have only one address. The problem with multiple PCs using one IP address is that you need some kind of address translation that will route traffic to/from your PCs accordingly.


Single IP Address Sharing

Hardware solution

The simplest and our recommended way to share your Internet connection across multiple PCs is by using a broadband router, you might want to check the Reviews section of the site for different brands and variations. The router sits between your external Cable/DSL modem and the LAN, or client PCs. Most Home/SOHO routers  are simple to setup and use, it's just a little more involved than plugging the unit in.

Generally, you might want to get a router with multiple LAN ports, so you can connect all your client PCs without additional hardware, such as hub or switch. Other significant considerations should include support and downloadable firmware updates.

Depending on your confidence and experience, you might want to consider a more expensive unit that's more complicated, with flexible configuration that gives you total control, or you can choose a simpler, easy to configure and maintain router. Whatever choice you make, most standard internet applications will work without problem with any of the routers we've reviewed.


Software solution

If for some reason you don't want to use a router, there is a way to share your Internet connectin by using either Proxy or NAT (Network Address Translation) software. Also, you would have to designate one PC as the server, and another as a client, rather than plugging your Modem to a hub.

1. Install 2 NICs in the Server PC and one in the Client PC.

2. Connect one of the NICs in the Server to the Cable Modem/xDSL and the second NIC to your LAN, or client PC. You can use a hub only between the PCs, not between the Cable modem and the Server.

3. Install either NAT or Proxy software. The advantages of using proxy are that you can block ports and it's more customizable. The disadvantage is that most networking software might require special configuration in order to run. If you decide to use NAT, on the other hand, most of your software will work without additional configuration on the client PCs.

Note that with this setup your server PC will need to be powered-up in order for your client PCs to be able to access the Internet.

Recommended NAT software: Sygate Internet Gateway
Recommended Proxy: Wingate WinProxy


Multiple IP addresses

If you decide to purchase additional IP addresses for each PC on your LAN, your ISP might charge you anywhere between $0-$10 / month for the additional service. The advantage of this method is that you wouldn't have to install any additional software, and you can plug the Cable Modem directly to a hub, rather than having one of the PCs on-line as a server, or buying a router. The only disadvantage is the possible monthly fee. If you have multiple IP addresses, ask your ISP's Tech. Support to assist you with configuring your LAN to share the Internet connection.


  User Reviews/Comments:
by anonymous - 2007-08-13 13:47
There is a software called CCProxy those who wish to share internet connection in Windows platform can use there are others but this was simple to use and to share broadband on Linux any distribution you can use the squid service but depending upon the configuration you might need two lan cards one for Switch and one to be connected to modem since in linux drivers for USB modem are difficult to find the same can be done in Windows using two lan card
by ARKAIN101 - 2008-01-20 01:59
Another option to sharing an internet connection is via a wireless unit connected to the host or server computer without the use of a "ROUTER".

I have not heard of this being done, but it does work if you configure things in the right order and manner.

Next, Your client computer needs the ability to connect wirelessly. Most laptops do this stock. But, as for a PC, you may have to buy a USB wireless adapter or an internal device.

Next, You go to the host computer, then, open the "network connections" in the control panel, select "properties" on the wireless and click the advanced tab. You need to have an option to "share this internet connection". If it is not there, it is because you have already set this to your current internet connection.

When you get this option there, click on the "settings" button and check the following boxes. This takes you to the services users can access..

check the box of DHCP (67) and (68)
check the box of UPnP (TCP) and (UDP)

save these settings.

Then find your true connection to the internet... and tell it to share..

This is what I did and I am sharing internet to anyone who connects to my wireless network.

My server is a measly USB Dlink wireless adapter and it works great.
by anonymous - 2009-09-10 02:35
sharing internet connections in a LAN is vital for companies and that's what you would expect from a proxy server. These days these solutions come with much additional functionality like a corporate firewall, antivirus, web server, mail server and NAT technology of course. I personally use ideco gateway but there are many other solutions of course
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