Internet security is a key issue for network engineers and monitoring hacking attempts is crucial. The fact that you only need to be in the networls proximity to get access means that hackers will attempt to breach your security. Changing authentication keys, regular audits and bandwidth monitoring are essential.
Wireless security
Change authentication and encryption keys regularly to prevent security breaches.
Using special characters and maximum length passwords will go a long way to securing your network.
Regularly change pass keys, use MAC filtering as well as a restricted DHCP server to secure your network.
Your data is irreplaceable so back it up, it is not something we all do regularly enough.