  Since ZMap's debut in 2013, networking and security researchers have used the
open-source scanner to write hundreds of research papers that study Internet
behavior. In addition, ZMap powers much of the attack-surface management and
security ratings industries, and more than a dozen security companies have
built products on top of ZMap. Behind the scenes, much of ZMap's behavior -
ranging from its pseudorandom IP generation to its packet construction - has
quietly evolved as we have learned more about how to scan the Internet. In this
work, we quantify ZMap's adoption over the ten years since its release,
describe its modern behavior (and the measurements that motivated those
changes), and offer lessons from releasing and maintaining ZMap.
