Perhaps by accident, you've gained access to someone else's Wi-Fi network. While you mean no harm, this clearly shows how wi-fi network can be unsecured at times. To avoid intrusion and illegal access to your wi-fi, here are some reminders:
Encryption for your wireless network
Encryption for your wireless network can be your best line of defense. Make sure that the encryption is turned on, whether you're using the Wireless Protected Access or Wireless Encryption Protocol. Use a password that won't easily be cracked or hacked by combining both letters and numbers. Also replace the default network name.
Firewall for your Wi-Fi Internet
Be sure to install a firewall to prevent intruders from getting unauthorized access. Though this cannot fully block illegal access to your network, you need all the extra protection you can get. Consider running software firewalls on each computer on your network.
Other security measures for wireless Internet access
Turn off your wireless card when you're done using the Internet connection. Before you log in to a public hotspot, check first if the network is legit through its name and log in date fields. Don't access important files in unsecured networks.
