Workflow

What is workflow?

- A series of steps are executed follow a certain order.

How to describe a workflow?
- Using a certain workflow meta data.
- Just one style: automate.

Microsoft phân biệt 2 types of workflow: sequential & state machine. What are the differences between them?

What is automaton?

Automata Theory

It must have

1. Workflow meta data.
2. Exception handling.
   
1. Exception detector
2. Exception handler
1. Update instance state
2. Modify workflow schema: Modification language

1. Migration: Automatically generate workflow handler schema.
   Ex: Adding compensation activity (2006.Efficient Handling of Changes in Dynamic Workflow Systems)
2. Fault tolerance
   

1. SOA
   
2. BPMN-BPEL
   
3. Windows Workflow Foundation (http://msdn2.microsoft.com/en-us/netframework/aa663328.aspx)
4. K2
5. Biztalk
6. Dotnet