Remoting Activation in VB.Net
The .NET Remoting framework supports both Server and Client activation of Remote Objects, providing flexibility in how objects are created and initialized for remote access. The activation process is essential before an object instance of a Remotable type can be accessed and utilized.
Server Activation and Client Activation
There are two commonly used activation modes: Server Activation and Client Activation. Server activation is typically employed when a Remote Object does not require the preservation of state between method calls. In this mode, the server creates and initializes the object upon request from the client, executes the desired method, and subsequently destroys the object. This approach ensures a stateless interaction and simplifies resource management on the server side.
On the other hand, Client Activated objects are instantiated from the client side, and the client retains control over the lifetime of the Remote Object. The client manages the object's existence using a lease-based system, ensuring its availability and appropriate cleanup. This activation mode is suitable when there is a need for specific client interaction or when stateful communication is required between the client and the Remote Object.
SingleCall Objects and Singleton Objects
Within the Server Activation mode, two subtypes exist: SingleCall Objects and Singleton Objects. SingleCall objects are created for each method call, executed, and subsequently destroyed, allowing for a fresh instance for every invocation. On the other hand, Singleton objects maintain a single instance throughout their lifecycle, serving as a shared resource accessible by multiple clients. This mode is advantageous when maintaining shared information or resources between clients is necessary.
It is important to note that the distinction between Client Activated and Server Activated objects lies in the creation process. With server-activated objects, the actual instantiation occurs when a client invokes it, rather than at the time of client instantiation. This on-demand creation approach optimizes resource utilization and allows for dynamic allocation based on client requests.
Conclusion
The .NET Remoting framework provides the flexibility of Server and Client activation modes for Remote Objects. Server activation is suitable for stateless operations, while Client activation allows for client-managed object lifetimes. SingleCall and Singleton objects cater to different usage scenarios within Server Activation mode. Understanding and selecting the appropriate activation mode is essential for efficient resource management and ensuring optimal communication between clients and Remote Objects.