Transcript Distributed Component Object Model (DCOM)

Distributed Component Object
Model (DCOM)
By
Deepak Goel & Mukesh Punhani
Component Software Problem
 Interoperability
 Versioning
 Language Independence
Transparency
Why Distributed Applications ?
Inherently Distributed
Flexibility
Scalability
COM Architecture
COM Components in the same process
COM components in different processes
DCOM Architecture
DCOM : COM components on different machines
Components Reusability
 Using Existing Components to Reduce
Development Cost
 Future Reusability of Components being
Developed
Language Neutrality
 Virtually all languages such as Java, Visual
C++, Visual Basic, Delphi, PowerBuilder,
COBOL interact well with DCOM
 Enables Rapid Prototyping
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
Scalability
Parallel Deployment
Scalability
Isolating Critical Components
Scalability
Pipelining
Security
 Provides Security at Component Level and
Method Level
 Uses Access Control Lists (ACL) similar to
Windows NT File System
Security
Per Interface Security using Registry Keys
Load Balancing
 Static Load Balancing
 Dynamic Load Balancing
Platforms
 UNIX/Mainframe
 Apple Macintosh
 Windows
 Java
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
Performance
Parameter Size
In-Process
Cross Process
Remote Call
4 Bytes
0.00031
0.42
2.7
50 Bytes
0.00031
0.49
3.27