Bring Your Own Device (BYOD) has been an increasingly popular concept for a few years, but its important to make sure your have proper security protocol in place before allowing unknown devices onto your network.
You must have a secure way to register these devices you don't own. Using Role Based Access Control, you can delineate your network access and configure different permissions for the variety of users and devices connecting to your network.
Don't be afraid of BYOD, be prepared. Learn more.