It is a \u201cmessage broker\u201d software library<\/strong> developed to make communications between distributed applications easier to program. We already mentioned that ODR-mmbTools consist of separate software modules on the same or different computers. These modules need a way to communicate and exchange data with each other.<\/p>\n\n\n\n ZeroMQ<\/strong> is the communication library that makes inter-application communication easier to program. The library contains sockets and is available for several programming languages.<\/p>\n\n\n\n The library makes an abstraction of the underlying complexity of communication protocols. The \u00d8 or zero stands for no broker. Indeed, no message broker (third-party software) is visible to the programmer because he uses only the offered ZeroMQ<\/strong> sockets.<\/p>\n\n\n\n \u201cMessage Queue\u201d stands for queuing messages. For example, the client can start sending messages even when the receiving server is not running. As soon as the server comes online, the queued message transfer begins. The programmer is not bothered with providing additional queue software because ZeroMQ<\/strong> handles it.<\/p>\n\n\n\n Without ZeroMQ<\/strong> and the provided queues, the program would give an error when the server is not running. ZeroMQ will also restart some processes automatically. ZeroMQ<\/strong> takes a lot of burdens away when programming inter-application communication software.<\/p>\n\n\n\n The complexity goes away for the programmer by using the ZeroMQ<\/strong> library.<\/p>\n\n\n\n