IPC basics

Question 1

What are the 5 types of middleware?

Answer 1

1. Transaction-oriented
2. Procedure-oriented
3. Object-oriented
4. Message-oriented
5. Service-oriented

Question 2

What are the advantages of Transaction-Oriented middleware?

Answer 2

• Provides ACID properties across distributed database

- Perform transaction across distributed machines

Question 3

What are the disadvantages of Transaction-Oriented middleware?

Answer 3

• Doesn’t scale

- Components are large-grained

Question 4

What are the advantages of Procedure-Oriented middleware?

Answer 4

• Make remote call (abstraction)

- Encourages distribution

Question 5

What are the disadvantages of Procedure-Oriented middleware?

Answer 5

• Tight binding
• Can’t reliably detect failure
• Language dependent

Question 6

What are the advantages of Object-Oriented middleware?

Answer 6

• Encapsulated state
• Strong interfaces which define ways to access the objects
• No explicit de-allocation

Question 7

What are the disadvantages of Object-Oriented middleware?

Answer 7

• Challenging to develop IDL

- Need to find a uniform way to interact with object references

Question 8

What are the advantages of Message-Oriented middleware?

Answer 8

• Location transparent
• Provides an abstraction for routing
• Asynchronous
• Dynamically add new components (more specialised)
• Define QoS guarantees

Question 9

What are the disadvantages of Message-Oriented middleware?

Answer 9

• Sender doesn’t know if their message has been received
• Can only be tackled at a system level
• Potentially more complex function in the server

Question 10

What are the advantages of Service-Oriented middleware?

Answer 10

• No notion of state

- Services are accessed using endpoints

Question 11

What are the disadvantages of Service-Oriented middleware?

Answer 11

• Heavy messages because state is in messages
• Less intuitive
• Doesn’t map to every application