WCF offers surpport for reliabilty, transactions, concurrency mgmt, security and instance activation, all of which rely on the wcf interception based architecture.Having a client interact with service(proxy) means that wcf is alwyas present between the client and the service , intercepting the call and performing precall and pos call processing.the interception starts whne the proxy serializes the call stack frame to the message and send the message down a chanin of cahnnels. each clients ide channel does a precall processing of the message. the last cahnne is the transport channel, whcih sends the messagge over the configured transport to the host.
on the host side, the msg goes thru another chain of channels theat perform host sie precall processing of the message. the first channel being transport channel which reciees he message from client transport. subsequent channel perform various task, like decryption of the message body, decoding of the mesg,joining the propgated transaction,setting the security principal, managing the session, and activating the service instance.
The last channel passes the msg to the dispatcher. the dispatcher convers the mes to the stack frame and calls the service instance.
The interception both on the client and service side ensurers theat the client and the service get the runtime environment they require to operate properly.
The service instance execules the call and returns control to the dispatcher which then converts the returned values and error inform into ta return messagae. the dispatcher then passes mesage to the hostside channels to perform post call processingg such as managing the trancasction, deactivating the instance, encoding the reply, encrypting it .. the returned mes goes the transport channel on the client side for post call processing. whcih consists of decrypting , decoding, committing or aborting the transcation... the last channel passes the message to the proxy , which converts the returned mesg to ta stack frame and returns the control to the client.
on the host side, the msg goes thru another chain of channels theat perform host sie precall processing of the message. the first channel being transport channel which reciees he message from client transport. subsequent channel perform various task, like decryption of the message body, decoding of the mesg,joining the propgated transaction,setting the security principal, managing the session, and activating the service instance.
The last channel passes the msg to the dispatcher. the dispatcher convers the mes to the stack frame and calls the service instance.
The interception both on the client and service side ensurers theat the client and the service get the runtime environment they require to operate properly.
The service instance execules the call and returns control to the dispatcher which then converts the returned values and error inform into ta return messagae. the dispatcher then passes mesage to the hostside channels to perform post call processingg such as managing the trancasction, deactivating the instance, encoding the reply, encrypting it .. the returned mes goes the transport channel on the client side for post call processing. whcih consists of decrypting , decoding, committing or aborting the transcation... the last channel passes the message to the proxy , which converts the returned mesg to ta stack frame and returns the control to the client.
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