.NET Remoting
Encyclopedia
.NET Remoting is a Microsoft
application programming interface
(API) for interprocess communication
released in 2002 with the 1.0 version of .NET Framework
. It is one in a series of Microsoft technologies that began in 1990 with the first version of Object Linking and Embedding
(OLE) for 16-bit Windows
. Intermediate steps in the development of these technologies were Component Object Model
(COM) released in 1993 and updated in 1995 as COM-95, Distributed Component Object Model
(DCOM), released in 1997 (and renamed Active X), and COM+ with its Microsoft Transaction Server
(MTS), released in 2000. It is now superseded by Windows Communication Foundation
(WCF), which is part of the .NET Framework 3.0.
Like its family members and similar technologies such as Common Object Request Broker Architecture
(CORBA) and Java's remote method invocation
(RMI), .NET Remoting is complex, yet its essence is straightforward. With the assistance of operating system and network agents, a client process sends a message to a server process and receives a reply.
(termed remotable object) available across remoting boundaries, which includes different appdomains, processes
or even different computers connected by a network. The .NET Remoting runtime hosts the listener for requests to the object in the appdomain of the server application. At the client end, any requests to the remotable object are proxied by the .NET Remoting runtime over
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
application programming interface
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
(API) for interprocess communication
Inter-process communication
In computing, Inter-process communication is a set of methods for the exchange of data among multiple threads in one or more processes. Processes may be running on one or more computers connected by a network. IPC methods are divided into methods for message passing, synchronization, shared...
released in 2002 with the 1.0 version of .NET Framework
.NET Framework
The .NET Framework is a software framework that runs primarily on Microsoft Windows. It includes a large library and supports several programming languages which allows language interoperability...
. It is one in a series of Microsoft technologies that began in 1990 with the first version of Object Linking and Embedding
Object Linking and Embedding
Object Linking and Embedding is a technology developed by Microsoft that allows embedding and linking to documents and other objects. For developers, it brought OLE Control eXtension , a way to develop and use custom user interface elements...
(OLE) for 16-bit Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
. Intermediate steps in the development of these technologies were Component Object Model
Component Object Model
Component Object Model is a binary-interface standard for software componentry introduced by Microsoft in 1993. It is used to enable interprocess communication and dynamic object creation in a large range of programming languages...
(COM) released in 1993 and updated in 1995 as COM-95, Distributed Component Object Model
Distributed component object model
Distributed Component Object Model is a proprietary Microsoft technology for communication among software components distributed across networked computers. DCOM, which originally was called "Network OLE", extends Microsoft's COM, and provides the communication substrate under Microsoft's COM+...
(DCOM), released in 1997 (and renamed Active X), and COM+ with its Microsoft Transaction Server
Microsoft Transaction Server
Microsoft Transaction Server was software that provided services to Component Object Model software components, to make it easier to create large distributed applications. The major services provided by MTS were automated transaction management, instance management and role-based security...
(MTS), released in 2000. It is now superseded by Windows Communication Foundation
Windows Communication Foundation
The Windows Communication Foundation , previously known as "Indigo", is an application programming interface in the .NET Framework for building connected, service-oriented applications.-The architectures:...
(WCF), which is part of the .NET Framework 3.0.
Like its family members and similar technologies such as Common Object Request Broker Architecture
Common Object Request Broker Architecture
The Common Object Request Broker Architecture is a standard defined by the Object Management Group that enables software components written in multiple computer languages and running on multiple computers to work together .- Overview:CORBA enables separate pieces of software written in different...
(CORBA) and Java's remote method invocation
Java remote method invocation
The Java Remote Method Invocation Application Programming Interface , or Java RMI, is a Java application programming interface that performs the object-oriented equivalent of remote procedure calls ....
(RMI), .NET Remoting is complex, yet its essence is straightforward. With the assistance of operating system and network agents, a client process sends a message to a server process and receives a reply.
Overview
.NET Remoting allows an application to make an objectObject-oriented programming
Object-oriented programming is a programming paradigm using "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction,...
(termed remotable object) available across remoting boundaries, which includes different appdomains, processes
Process (computing)
In computing, a process is an instance of a computer program that is being executed. It contains the program code and its current activity. Depending on the operating system , a process may be made up of multiple threads of execution that execute instructions concurrently.A computer program is a...
or even different computers connected by a network. The .NET Remoting runtime hosts the listener for requests to the object in the appdomain of the server application. At the client end, any requests to the remotable object are proxied by the .NET Remoting runtime over
Channel objects, that encapsulate the actual transport mode, including TCPTransmission Control ProtocolThe Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...
streams, HTTP streams and named pipeNamed pipeIn computing, a named pipe is an extension to the traditional pipe concept on Unix and Unix-like systems, and is one of the methods of inter-process communication. The concept is also found in Microsoft Windows, although the semantics differ substantially...
s. As a result, by instantiating proper Channel objects, a .NET Remoting application can be made to support different communication protocols without recompiling the application. The runtime itself manages the act of serializationSerializationIn computer science, in the context of data storage and transmission, serialization is the process of converting a data structure or object state into a format that can be stored and "resurrected" later in the same or another computer environment...
and marshallingMarshalling (computer science)In computer science, marshalling is the process of transforming the memory representation of an object to a data format suitable for storage or transmission...
of objects across the client and server appdomains.
.NET Remoting makes a reference of a remotable object available to a client application, which then instantiates and uses a remotable object as if it were a local object. However, the actual code execution happens at the server-side. A remotable object is identified by Activation URLUniform Resource LocatorIn computing, a uniform resource locator or universal resource locator is a specific character string that constitutes a reference to an Internet resource....
s and are instantiated by a connection to the URL. A listener for the object is created by the remoting runtime when the server registers the channel that is used to connect to the remotable object. At the client side, the remoting infrastructure creates a proxy that stands-in as a pseudo-instantiation of the remotable object. It does not implement the functionality of the remotable object, but presents a similar interface. As such, the remoting infrastructure needs to know the public interface of the remotable object before-hand. Any method calls made against the object, including the identity of the method and any parameters passed, are serializedSerial communicationIn telecommunication and computer science, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels...
to a byte stream and transferred over a communication protocol-dependent Channel to a recipient proxy object at the server side ("marshalledMarshalling (computer science)In computer science, marshalling is the process of transforming the memory representation of an object to a data format suitable for storage or transmission...
"), by writing to the Channel's transport sink. At the server side, the proxy reads the stream off the sink and makes the call to the remotable object on the behalf of the client. The results are serialized and transferred over the sink to the client, where the proxy reads the result and hands it over to the calling application. If the remotable object needs to make a callback to a client object for some services, the client application must mark it as remotable and have a remoting runtime host a listener for it. The server can connect to it over a different Channel, or over the already existent one if the underlying connection supports bidirectional communication. A channel can be composed of a number of different Channel objects, possibly with different heterogeneous transports. Thus, remoting can also work across systems separated by an interconnection of heterogeneous networks, including the internet. Type safetyType safetyIn computer science, type safety is the extent to which a programming language discourages or prevents type errors. A type error is erroneous or undesirable program behaviour caused by a discrepancy between differing data types...
is enforced by the CTSCommon Type SystemIn Microsoft's .NET Framework, the Common Type System is a standard that specifies how Type definitions and specific values of Types are represented in...
and the .NET Remoting runtime. Remote method calls are inherently synchronous; asynchronous calls can be implemented using threading libraries. Authentication and access control can be implemented for clients by either using custom Channels or by hosting the remotable objects in IISInternet Information ServicesInternet Information Services – formerly called Internet Information Server – is a web server application and set of feature extension modules created by Microsoft for use with Microsoft Windows. It is the most used web server after Apache HTTP Server. IIS 7.5 supports HTTP, HTTPS,...
and then using the IIS authentication system.