Atomicity

1.Logging: record your logs, and restore if problems occur
2.shadow paging: modify the copy of page (few systems do this, slow)

Consistency

Database consistency
Transaction consistency: application's responsibility

Isolation

interleave txn
Use concurrency control to ensure Isolation. Protocols:
1.Pessimistic: leave the problems where they are
2.Optimistic: deal with them
Correctness: equivalent serial schedule
Interleaving Conflicts: RW WR WW
equivalent conflicts

Duration