Distributed Object Middleware (DOM)
This type of infrastructure allows to access remote objects transparently. It is based on the Remote Procedure Call (RPC) mechanism e.g., CORBA, Microsoft’s DCOM, or EJB (Enterprise Java Beans) by Sun Microsystems.
Message Oriented Middleware (MOM)
MOM systems offer functionalities for asynchronous transmission of messages. MOM ensures that messages are delivered nevertheless. Examples of MOM systems include Sun’s JMS (Java Messaging Service) and Microsoft’s MSMQ (Microsoft Message Queue).