COM+

(Review) What is COM+

1. Evolutionary step, making it even easier to build and use components

2. Infrastructure in the system, not in the application

3. Extensible services

4. Preserves current investments in COM

5. Provides benefits across languages and tools

6. Less coding, more productivity

More:

• Built on the the foundation of COM
• With COM evolved, the ability to distribute functionality among machines was added based on DCOM
• Microsoft's distributed object transport protocol was based on Remote Procedure Calls (RPC)
• MTS is on top of COM
•    Provides transaction support, ORB-style instantiation, and component wrapper
•    Provides a declarative syntax for defining transaction and security requirements, which is complex and error-prone
•    To deliver scalability, MTS relies on Just-In-Time (JIT) instantiation and ASAP destruction of COM object instances
•    Doesn't fit in all requirements
• COM+ delivers more fine-grained control in addition to new feature and services
• COM+ intended to operate under multi-tier Distributed Networking Application Architecture (DNA)