When you shop online and enter credit card information for payment, clicking "submit" sends a message to the server to process your payment information. RabbitMQ is a "broker" that handles these messages. It is open source software, meaning that it can be modified by anyone knowledgeable in computer coding. Computers using RabbitMQ must have their ports configured to allow the program to send messages over a network. Ports are simply communications channels between computers.
RabbitMQ and Developers
RabbitMQ makes it easier for application developers to create programs to their exact specifications. By using RabbitMQ, they do not have to worry about accommodating different operating systems and network interfaces with regard to messaging. Developers can decouple individual program components, with RabbitMQ handling the messaging between components.
Ports are connection channels between two machines over a TCP/IP or UDP network. Port 80 is a commonly used port that enables computers to send and receive Web traffic. Problems can arise when ports are blocked by a computer's network firewall or an end user fails to route a particular program through a port. For example, when sending and receiving e-mail, users must configure a third-party email program (such as Microsoft Outlook) to include a server port number. Without the proper port number configured, the user cannot connect to the server.
RabbitMQ requires only one port to connect. Port 5672 is the default port that the tool uses to connect to its various components. Developers must keep this port number in mind when they network RabbitMQ into their various applications.
If your computer runs the RabbitMQ application behind a firewall, you must open a port in your firewall application so that RabbitMQ will work properly. Instead of simply opening port 5672, the default port, you must use port 5672:tcp in your firewall application. Firewalls are programs that separate private networks (such as local area networks) from other networks (such as the World Wide Web).