JSTUN is a STUN (Simple Traversal of UDP (User Datagram Protocol) through NAT (Network Address Translation)) implementation. STUN provides a means for applications to discover the presence and type of firewalls or NATs between them and the public Internet. In the presence of a NAT, STUN can also be used by applications to learn the public Internet Protocol (IP) address assigned to the NAT.
JSend NSCA is a Java API and command line tool for sending Nagios Passive Checks to the Nagios NSCA add-on. By using the JSend NSCA core API, you can easily integrate your Java applications into a Nagios monitored environment, thereby notifying Nagios of problems and issues during the running of your application. The JSend NSCA CLI command line tool wraps the API and allows you to send passive checks from the command line.