Protecting your music online is indeed a crucial aspect. Firstly, ensure that your work is copyrighted. In many countries, your music is automatically copyrighted once it's in a tangible form, but officially registering the copyright can provide additional protection. You can also use digital rights management (DRM) systems available through various distribution services. Additionally, some online platforms have built-in measures to prevent illegal downloads and sharing. Lastly, you can use content identification systems like YouTube's Content ID to monitor and control where your music is used online.