Turning the Pi into a Wi-Fi hotspot

Let's say you're out in the field with a couple of fellow agents and you want to quickly put up a network for your computers, maybe even share an Internet connection together; your Pi equipped with a Wi-Fi dongle can easily be made into a makeshift access point. Follow these steps to set up your hotspot:

1. First install the required software with the following command:

   pi@raspberrypi ~ $ sudo apt-get install hostapd bridge-utils
   

2. Next we need to prevent Raspbian from interfering with the Wi-Fi interface. Open up /etc/network/interfaces for editing:

   pi@raspberrypi ~ $ sudo nano /etc/network/interfaces
   

3. Find the block that starts with allow-hotplug wlan0 and put a # character in front of each line, like we've done here:

   #allow-hotplug wlan0
   #iface wlan0 inet manual
   #wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
   #iface default inet dhcp

4. Optionally, if you would like to share a wired Internet connection with the wireless clients, add the following three lines...