Evolution of Remoting
(DCE), designed by the Open Software Foundation (OSF) during the early 1990s, was created to provide a collection of tools and services that would allow easier development and administration of distributed applications. The DCE framework provides several base services such as Remote Procedure Calls (DCE/RPC), Security Services, Time Services, and so on.
, is only a collection of standards; the implementation of object request brokers (ORBs) is done by various third parties. Because parts of the standard are optional and the vendors of ORBs are allowed to include additional features that are not in the specifications, the world has ended up with some incompatible request brokers. As a result, an application developed to make use of one vendor's features could not easily be ported to another ORB. When you buy a CORBA-based program or component, you just can't be sure if it will integrate with your CORBA applications, which probably were developed for a different request broker.
is an 'extension' that fits in the Component Object Model (COM) architecture, which is a binary interoperability standard that allows for component-oriented application development. You'll usually come in contact with COM when using ActiveX controls or ActiveX DLLs.
(MTS), was Microsoft's first serious attempt to reach into the enterprise application domain. It not only serves as a remoting platform, but also provides transaction, security, scalability, and deployment services. COM+ components can even be used via Microsoft Message Queue Server to provide asynchronous execution of methods.
(Java RMI) uses a manual proxy/stub compilation cycle. In contrast to DCE/RPC and DCOM, the interfaces are not written in an abstract IDL but in Java. This is possible due to Java being the only language for which the implementation of RMI is possible.
(EJB) was Sun's answer to Microsoft's COM+. Unlike CORBA, which is only a standard, EJB comes with a reference implementation. This allows developers to check if their products run in any standard-complying EJB container. EJB has been widely accepted by the industry, and there are several container implementations ranging from free open source to commercial implementations by well-known middleware vendors.
provided the first easy to understand and implement solution to true cross-platform and cross-language interoperability. Web Services technically are stateless calls to remote components via HTTP POST with a payload encoded in some XML format.
, defines a much richer set of services; the specification covers not only remote procedure calls, but also the (WSDL) and (UDDI). WSDL is SOAP's interface definition language, and UDDI serves as a directory service for the discovery of Web Services. Those additional protocols and specifications are also based on XML, which allows all SOAP features to be implemented on a lot of platforms.
(DCE), designed by the Open Software Foundation (OSF) during the early 1990s, was created to provide a collection of tools and services that would allow easier development and administration of distributed applications. The DCE framework provides several base services such as Remote Procedure Calls (DCE/RPC), Security Services, Time Services, and so on.
, is only a collection of standards; the implementation of object request brokers (ORBs) is done by various third parties. Because parts of the standard are optional and the vendors of ORBs are allowed to include additional features that are not in the specifications, the world has ended up with some incompatible request brokers. As a result, an application developed to make use of one vendor's features could not easily be ported to another ORB. When you buy a CORBA-based program or component, you just can't be sure if it will integrate with your CORBA applications, which probably were developed for a different request broker.
is an 'extension' that fits in the Component Object Model (COM) architecture, which is a binary interoperability standard that allows for component-oriented application development. You'll usually come in contact with COM when using ActiveX controls or ActiveX DLLs.
(MTS), was Microsoft's first serious attempt to reach into the enterprise application domain. It not only serves as a remoting platform, but also provides transaction, security, scalability, and deployment services. COM+ components can even be used via Microsoft Message Queue Server to provide asynchronous execution of methods.
(Java RMI) uses a manual proxy/stub compilation cycle. In contrast to DCE/RPC and DCOM, the interfaces are not written in an abstract IDL but in Java. This is possible due to Java being the only language for which the implementation of RMI is possible.
(EJB) was Sun's answer to Microsoft's COM+. Unlike CORBA, which is only a standard, EJB comes with a reference implementation. This allows developers to check if their products run in any standard-complying EJB container. EJB has been widely accepted by the industry, and there are several container implementations ranging from free open source to commercial implementations by well-known middleware vendors.
provided the first easy to understand and implement solution to true cross-platform and cross-language interoperability. Web Services technically are stateless calls to remote components via HTTP POST with a payload encoded in some XML format.
, defines a much richer set of services; the specification covers not only remote procedure calls, but also the (WSDL) and (UDDI). WSDL is SOAP's interface definition language, and UDDI serves as a directory service for the discovery of Web Services. Those additional protocols and specifications are also based on XML, which allows all SOAP features to be implemented on a lot of platforms.
