1. 4.3 Transaction Communication
Yichuan Wang

2. What is transaction Network Business[2006, Chun-I Fan etc.] Database
Communication
Web Service
Fair Transaction Protocols Based on Electronic Cash

3. Let’s jog memory The first presentation by Yang Wang
The Goal: Concurrency Transparency
What is it again?
Service Oriented Request/Reply
Multicast

4. Transaction
Come from the transaction concept in the Database Management System
A sequence of synchronous request/reply that satisfy ACID
In distributed communication
Use asynchronous request/reply and multicast that satisfy ACID[1997, Randy Chow etc.]?

5. ACID
Atomicity
Consistency
Isolation
Durability

6. Atomicity
All (success) or none (fail)
Why?

7. Concurrency? Or serializebility
Interleaved transactions is equivalent to a serial execution

8. Isolation
Partial result not visible until commit

9. Durability
After commitment, result is permanent even if system failed

10. Transaction Model Coordinator Participants
Commit or abort, based on whether conform to ACID
How?

11. Two-phase commit Protocol
2PC[wikipedia]
Like a vote

12. 2PC Coordinator Participants Basic Idea Logging, Shadow Caching
Time line

13. 2PC recovery on error cases
Log: old, new and vote.
Redo Only[2000, Mohammad Alrifai etc.]
Undo Only
Hybrid
Cascade rollback[wikipedia]

14. Problem with 2PC Uncertain time: lock
Non-Blocking: Asynchronous: not possible unless…
3PC[2004,Wenbing Zhao etc.]

15. Transaction in web service
from different trusted domain and use heterogeneous application logics, flows, and platforms.
the sub-transaction of each participant may execute for various periods of time.
we can’t just undo or roll back the whole transaction.

16. Reference
[1]Randy Chow etc.; Distributed Operating System & Algorithm; 1997
[2]Wenbing Zhao etc., A Reservation-Based Extended Transaction Protocol,2004
[3] Mohammad Alrifai etc., Transactions Concurrency Control in Web Service Environment,2000
[4] phase_commit_protocol
[5] Chun-I Fan etc., Fair Transaction Protocols Based on Electronic Cash, 2006
[6]