How does BGP work? Briefly, BGP allows the Internet to function, much like how this email arrived in your Inbox via SMTP. It's an effective security solution for protecting proprietary, non-HTTPS technology. In this post we explain in simple language, the history of topology in external protocol gateway (EPG) and how autonomous systems (AS) evolved into the mesh topology we use today. Then we dig in deeper showing how network prefix announcements allow independent autonomous systems to communicate uninterrupted, advertising the information you need at lightning speeds.