Name different instance modes in WCF.

1.	Name different instance modes in WCF.
Answer» WCF provides three ways to control WCF instance creation as follows: Per Call: A NEW instance will be created for each request from the same client or a new one, which means that every request will be a new request. Although this mode is most efficient in terms of MEMORY, a session still needs to be maintained. Per Session: A new instance would be created for each new client session, and the SCOPE of that OBJECT would correspond to the scope of that session. Single Instance: For each SERVICE object, only one instance will be created for all requests, regardless of whether they are coming from the same client or not. This is the least efficient instance mode in terms of memory usage.

Answer»

WCF provides three ways to control WCF instance creation as follows:

Per Call: A NEW instance will be created for each request from the same client or a new one, which means that every request will be a new request. Although this mode is most efficient in terms of MEMORY, a session still needs to be maintained.
Per Session: A new instance would be created for each new client session, and the SCOPE of that OBJECT would correspond to the scope of that session.
Single Instance: For each SERVICE object, only one instance will be created for all requests, regardless of whether they are coming from the same client or not. This is the least efficient instance mode in terms of memory usage.

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