<. Net distributed application development> Reading Notes Chapter 10: Q &

Q: What is the relationship between high performance and high scalability?
A: The relationship between the two is the same as that between the two. High-performance communication reduces scalability. High scaling means performance is reduced.

 

Q: When do I need to distribute data?
A: the following situations:
1. Integration with different racks, such as modifying old systems without source code. Integration of J2EE and. NET applications.
2. High Security requirements. Clients are not allowed to modify applications.Program.
3. Business logic is centrally managed on the app server.
4. Scaling is particularly important and supports access from many clients. Performance is not the most concerned, such as large B2C websites.

 

Q: What are the considerations for designing distributed components?
Answer: 1. Large-granularity APIs Minimize the number of data transfers.
2. Use statless objects whenever possible. This not only reduces server memory usage, but also supports load balancing.
3. Remote objects are not traditional OO objects, so do not bring the OO principles of desktop applications into distributed design.

 

Q: Why can't traditional OO designs be used?
A: This is because:
1. XML Web Service cannot save the object status.
2. XML Web Service returns XML, not an object.
3. Remote objects generally do not trigger events or transmit data in two directions.