'Asio' is a cross-platform C++ library for network and low-level I/O
programming that provides developers with a consistent asynchronous model using
a modern C++ approach. It is also included in Boost but requires linking when
used with Boost. Standalone it can be used header-only (provided a recent
compiler). 'Asio' is written and maintained by Christopher M. Kohlhoff, and
released under the 'Boost Software License', Version 1.0.