Design And Implementation Of Message-Oriented Middleware In Distributed System

Middleware is developed promptly and various Middleware standards were brought forward in recently years. Message-Oriented middleware (MOM) is a special middleware based on message-transmission, and it provides effective and reliable message transmission for communication across heterogeneous platforms. MOM services allow distributed application to locate transparently across the network, which provide interaction with another application or service, be independent from network services and scale up in capacity without losing function.ATC system is a large distributed system. Using MOM in ATC system can make the system development easier; make the system more stabile; improve the system’s capability; make the system’s maintenance easy and reduce the system development cost. Although the MOM will take large advantage for ATC system, the ATC system has strict request for the MOM which will use in it. The requests for the MOM mostly were real-time, stability, reliability and low-cost. So the MOM used in ATC system is different form the common MOM in designing and achieving.In the ATC system object, the author developed the first version of a MOM which is used in several different ATC systems. The author used the Data-Oriented method to develop the MOM. The developed MOM is fit for the ATC system and is will used in the real application.The MOM makes up of CDC (Consistence Data Copies) and MQM (Message Queuing Middleware).These two parts can independent run and apply there interface. The CDC supplies consistence data service. It will make the data copies on each node be same. The application can get the data copies’change event and operate the data copy on local node by using the interface supplied by CDC. Of course, these operations will affect other data copies at once; the applications on other node will get the change event, and if needed, the applications can get the new data. The MQM supplies data that have various attribute communication service for the applications. The MQM can supply agility service. Because of this, the applications can transmit any data which are not expected and can define the data timeliness, reliability, perpetuity, order attributes, and so on. The MQM will use different mode to transmit these data to content there attributes. The destination processes will receive right (right time, right place and right content) messages.