According to the glossary, "oneagentmon device” appears in your Windows system during Dynatrace OneAgent installation. It's used by Dynatrace for deep process monitoring. It works like a monitoring driver and allows Dynatrace OneAgent to add its own library between the operating system and processes it is running."
Have you also seen that doc page: OneAgent installation? Does it answer you question?
Hi Mounika. Just as Karolina stated above, OneAgentMon device is used in our automatic injection process. WinPcap is a driver that is used to capture network traffic. It is used by Network Agent, to calculate connectivity, per-PGI network traffic and generate network topology. Please let us know, if we can provide you with some further clarifications.