If you have a single wired Internet connection – say, in a hotel room – you can create an ad-hoc wireless network with Ubuntu and share the Internet connection among multiple devices. Ubuntu includes an easy, graphical setup tool.
Unfortunately, there are some limitations. Some devices may not support ad-hoc wireless networks and Ubuntu can only create wireless hotspots with weak WEP encryption, not strong WPA encryption.
Setup
To get started, click the gear icon on the panel and select System Settings.
Select the Network control panel in Ubuntu’s System Settings window. You can also set up a wireless hotspot by clicking the network menu and selecting Edit Network Connections, but that setup process is more complicated.
If you want to share an Internet connection wirelessly, you’ll have to connect to it with a wired connection. You can’t share a Wi-Fi network – when you create a Wi-Fi hotspot, you’ll be disconnected from your current wireless network.
To create a hotspot, select the Wireless network option and click the Use as Hotspot button at the bottom of the window.
You’ll be disconnected from your existing network. You can disable the hotspot later by clicking the Stop Hotspot button in this window or by selecting another wireless network from the network menu on Ubuntu’s panel.
After you click Create Hotspot, you’ll see an notification pop up that indicates your laptop’s wireless radio is now being used as an ad-hoc access point. You should be able to connect from other devices using the default network name – “ubuntu” – and the security key displayed in the Network window. However, you can also click the Options button to customize your wireless hotspot.
From the wireless tab, you can set a custom name for your wireless network using the SSID field. You can also modify other wireless settings from here. The Connect Automatically check box should allow you to use the hotspot as your default wireless network – when you start your computer, Ubuntu will create the hotspot instead of connecting to an existing wireless network.
From the Wireless Security tab, you can change your security key and method. Unfortunately, WPA encryption does not appear to be an option here, so you’ll have to stick with the weaker WEP encryption.
The “Shared to other computers” option on the IPv4 Settings tab tells Ubuntu to share your Internet connection with other computers connected to the hotspot.
Even if you don’t have a wireless Internet connection available to share, you can network computers together and communicate between them – for example, to share files.
source : http://www.howtogeek.com
