The Perform template std::async runs the function f asynchronously (probably in a separate thread which could be a Portion of a thread pool) and returns a std::future that should at some point maintain the results of that perform simply call. one) Behaves as if (2) is known as with policy https://alphawireless.com/future-proofing-american-utilities-why-900-mhz-is-critical-for-utility-communications/