Information on Replication and Security with PostgreSQL

Hi ,

I search more info about : Replication and Security With PostgreSQl:
Questions are listed bellow :

**Replication :* *

*Type of Replication* :
Master-Slave, Multi-Master, Others ..

**Maximum of Servers/Slaves ?:* *

**Replication other WAN (TCP-IP)**
Available : Yes/No Why?

*Performance Consideration*
Have you a comment on Performace eg Type of line used for communication
? ...

*Limitations*
Let me Know if PostgreSQL have any limition on Replication

*Automatic Replication after Network Failure*
Have you a tool, to restore automatically replication after a breakdown
of Internet, or link (VPN, ....)

**Others Comments (if you have ?) *
*

*Security*:

To analyse PostgerSQL through the following 3 requirements:

*1. Authentication *
integration with existing authentication such as Windows, Kerberos, etc.

*2. Authorisation *
How does the app/db restrict access rights to certain group of users

*3. Accountability *
Audit trail - linking users to all transactions.

Thanks for your quick answer,

Regards,
Serge PERRIER