WCF - Questions to be answered when implementing

What are the questions that you need to answer and consider when creating a WCF service?

ServiceContract

• What service contracts do I need?
• What SessionMode (Allowed/NotAllowed/Requied) do I need to support for my service contract?
• What ProtectionLevel my service contract needs (None/Sign/EncryptAndSign)?
• Do I need to support CallbackContract?

ServiceBehaviour

• Which ServiceContract my ServiceBehaviour needs to implement?
• Which AddressFilterMode do I need for my ServiceBehavoir (Any/Exact/Prefix)?
• Which ConcurrencyMode do I need for my ServiceBehavior (Multiple/Reentrant/Single)?
• Which InstanceContextMode do I need for my ServiceBehavior (PerCall, PerSession, Single)?

EndPoint and Binding

• What are the endpoints I want to expose? How many? (which address, binding, contract)
• What are the bindings I want to have? e.g. basicHttpBinding, wsHttpBinding
• What security mode my binding should have? e.g. None/Message/Transport level security

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