1.In client/server architecture, the server contains the Application data
2.In two-tier architecture, the business logic is handled by the Client
3.In three-tier architecture, the data required by the application is stored on the Database server.
4.N-tier architecture can contain any number of application servers.
5.Proxy is a helper object created on clients and servers.
6. Marshalling refers to converting the request and response into a format that can be transferred across a network.
7. DCOM stands for distributed COM.
8. DCOM uses ORB to enable components to communicate across a network.
Introduction to COM
1.Com is a binary standard.
2. COM creates two helper objects Stub and Proxy
3. COM is a component software architecture which defines a set of Application Programming Interface (API).
4. An Interface is the only point of contact between clients and the objects in COM.
5. The process of sending packaged method calls across process or machine boundaries in binary format is called Marshalling.
6. GUID is a 128 bit value.
7. A client and server running on different process can communicate through RPC.
8. Macros are used by COM to extract fields form HRESULT
9. All objects in COM must implement thee IUnknown interface.
10. An interface in COM is Immutable.
11. In an IUnknown interface, Addref() Increment the reference counter.
12. In an IUnknown interface, Release() Decrement the reference counter.











