Inbound traffic engineering (ITE)—the process of announcing routes
to, e.g., maximize revenue or minimize congestion—is an essential
task for Autonomous Systems (ASes). AS Path Prepending (ASPP) is
an easy to use and well-known ITE technique that routing manuals
show as one of the first alternatives to influence other ASes’ routing
decisions. We observe that origin ASes currently prepend more than
25% of all IPv4 prefixes.