First step: I have to make the wireless ethernet card start to work for my Lenovo W520 with Debian installed. Initially, I installed the package firmware-iwlwifi, which contains the firmware for Intel Wireless 1000 inside Lenovo W520. However, only with this firmware, the wireless ethernet card still couldn‘t be recognized. Then, I downloaded compat-wireless-3.6.6-1.tar.bz2. After compilation and installation (note: to compile this package, the linux-headers should be installed), the Intel Wireless ethernet card started normally! With a full gnome desktop environment installed, which contains the gnome-desktop-environment package, an icon for the network connection (this is the network-manager-gnome package) will be displayed in the top panel, from which we can find wireless network access point. However, if there is no such desktop environment, commands can still be used to connect to the internet. This web page contains a full list of related commands, which is quite helpful. To have some of the wireless related commands available on your system, wireless-tools package should be installed. Then, the following procedures can be used to start a WLAN connection:

1. Activate the wireless ethernet card

   ifconfig [interface] up

   Here [interface] is usually wlan0.

2. Get a list of available access points

   iwlist [interface] scan

3. Specify essid of the WLAN

   iwconfig [interface] essid “essid name”

4. Get a IP address

   dhclient [interface]

Second step: I should have a permanent internet access point wherever I go. In Switzerland, there are three communication companies: Swisscom, Sunrise and Orange. Swisscom is just like China Mobile, which is the most expensive, but has the best performance. However it also has the strictest requirements on your residence permit. So normally for a short period of residence in Switzerland, you do not have the rights to apply a cost efficient and fast speed internet access. For the Orange, it is the cheapest but has poor net speed according to some forum. Therefore, I finally selected Sunrise SIM card for mobile with 2.5 MB/s 3G network transfer speed and 1GB data volume per month, which costs only 19 CHF per month. Meanwhile, you will also get a local mobile phone number, With this number, you can receive the access password for public WLANs. I am also excited to find out that iPhone has a function named Personal Hotspot, which can transform your iPhone into a wireless router.

Now, I can use Skype on iPhone to make internal phone call and in the meantime surf the internet using iPhone wireless hotspot. This is so great!