Overview:

Internet Connection Sharing (ICS), a feature which has been available in Microsoft Windows Operating System since the deployment of Windows 98 second edition, allows sharing of internet connection from a host. ICS provides NAT – network address translation and the reconciliation of an IP address to a user-friendly computer name.

How ICS Works

The designated computer from which internet would be shared, known as the host or server, must have at least two network interfaces. One interface which connects directly to the internet and another which connects to the LAN of ICS clients. The interface on the host which connects directly to the internet may be either of the following; a dial-up modem – even though not mostly used, a wireless adapter or card, a USB interface – for GSM modems, or an Ethernet interface. As shown below, internet connection to all ICS clients will fail when the host or server loses internet connectivity.


Figure 1. – ICS clients sharing internet connection from an ICS host or server

ICS clients connect to the internet using the single IP assigned to the server by the Internet Service Provider – ISP. This is achieved through a process called Network Address Translation – NAT. The advantage of ICS is that there is no need to purchase a router as the ICS host/server performs NAT. One disadvantage is that the absence of a router prevents advanced configurations from being achieved.

How to Set up Internet Connection Sharing on Windows 7


Here, all the adapters and interfaces will be visible.


Right-click and select properties on the interface which connects directly to the internet. In this case, the wireless interface.


Once the network adapter’s properties window appears, select on the Sharing tab, then click on “Allow other network Users to connect through this computer’s internet connection.”

It is important to verify that ICS is enabled on the network interface that connects directly to the internet.


To secure the ICS host or server, the following options must be unchecked or disabled; client for Microsoft networks and File & printer sharing for Microsoft networks.


All ICS clients will have internet connectivity once the ICS host is connected to the internet.

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Limitations of ICS

Even though ICS introduces a cost saving method for sharing internet across multiple devices known as ICS clients, it has the following limitations:

No filtering of specific IPs and URLs for ICS clients.

No filtering of specific TCP ports for ICS clients.

No Bandwidth management for ICS clients.

How to Start and Stop ICS from services.msc

The following steps provide a brief method to either start or stop Internet Connection Sharing from services.msc

From the start button, type services.msc


And press enter to search for it


Double click Internet Connection Sharing(ICS)


From the General tab, the start-up type can be changed, and the service started or stopped.

Windows Utilities to manage ICS Processes.

Due to the limited capabilities of Windows ICS, utilities such as My Public WiFi, Ositis WinProxy, Connectify Hotspot, and Virtual Router Managers are amongst software tools deployed to provide additional functions in managing the ICS clients. This article will describe briefly how My Public WiFi works.

My Public WiFi Utility

This free utility is a software with the capability to turn a computer or smartphone into a wireless hotspot.

Downloading My Public WiFi

The utility of size 1MB can be downloaded from http://www.mypublicwifi.com/publicwifi/en/index.html

Setting up My Public WiFi

After installing the utility, it can be setup using procedures below:

  1. Launch the software


  1. Under “Settings” tab, select Automatic Hotspot configuration and set Network Name or SSID
  2. Set password for the wireless network to be broadcast
  3. Select the network interface which is directly connected to the internet. The interfaces may be one of as shown below and would be same as the network interfaces identified under Network Connections.

    My Public WiFi


Network Connections


  1. After selecting the interface type, internet sharing must be enabled
  2. Select Setup and Start Hotspot
  3. Internet will be available on all the ICS clients once the ICS host or server has internet.

Firewall Function in MyPublicWiFi

The firewall function in MyPublicWiFi utility can be used to prevent users’ specific servers and internet services, including file sharing programs, which go a long way to save bandwidth.

URL Logging Function in MyPublicWiFi

The logging function in MyPublicWiFi is used to track all sessions actioned by users connected to the hotspot. These tracking sessions include URLs visited, their respective MAC addresses and time stamps.

Conclusion

Internet Connection Sharing provides computers within a network with the ability to share a single internet connection. This article has briefly explained how ICS works using either a USB modem, wireless connection, or internet connection from a LAN switch. It has also explained how to setup ICS on Windows stating its limitations. And finally, introduced MyPublicWiFi as a Windows utility which manages ICS with the added functionality of URL logging and Firewall function preventing ICS clients from visiting specific websites thereby saving bandwidth.