1. Distributed Component Object Model (DCOM)By
Deepak Goel & Mukesh Punhani

2. Component Software Problem
Interoperability
Versioning
Language Independence
Transparency

3. Why Distributed Applications ?
Inherently Distributed
Flexibility
Scalability

4. COM Architecture COM Components in the same process
COM components in different processes

5. DCOM : COM components on different machines
DCOM Architecture
DCOM : COM components on different machines

6. Components Reusability
Using Existing Components to Reduce Development Cost
Future Reusability of Components being Developed

7. Language Neutrality
Virtually all languages such as Java, Visual C++, Visual Basic, Delphi, PowerBuilder, COBOL interact well with DCOM
Enables Rapid Prototyping

8. Location Independence
Components that interact more should be closer to each other
Some components can only be run on specific machines
Small Components : Easy to Deploy - Increased Network Traffic
Large Components : Difficult to Deploy - Reduced Network Traffic

9. Scalability
Parallel Deployment

10. Isolating Critical Components
Scalability
Isolating Critical Components

11. Scalability
Pipelining

12. Security Provides Security at Component Level and Method Level
Uses Access Control Lists (ACL) similar to Windows NT File System

13. Per Interface Security using Registry Keys

14. Load Balancing
Static Load Balancing
Dynamic Load Balancing

15. Platforms
UNIX/Mainframe
Apple Macintosh
Windows
Java

16. Comparison with CORBA and RMI
DCOM fits best with Microsoft Platform i.e. Windows 98 and Windows NT while CORBA is quite general.
RMI works only with Java but is quite suitable when application wants to exploit features of Java

17. Performance Parameter Size 4 Bytes 50 Bytes In-Process 0.00031 0.00031
Cross Process
Remote Call