Consistency
In order to have a consistent data, we always have to synchronize multiple copies of the same data.
| Weak Consistency | Eventual Consistency | Strong Consistency | |
|---|---|---|---|
| After a write | reads may or may not see it | reads eventually will see it | reads will see it |
| Scenario | Real time cases such as VoIP, video chat | DNS and Email | Need Transactions system: file systems and RDBMSes |