What should be the ideal network configuration for a Postgresql Streanming Replication and PgPool HA setup

I have the following configuration using Pgpool, Postgresql with streaming replication. Pgpool is used for load balancing and automatic failover.

   .-----.                  .--------.
   |     |           W      |   DB   |
   | PGP |-----+----------->| MASTER |----.
   |     |     |            |        |    |
   `-----`     |            `--------`    | STREAMING REPLICATION
               |            .--------.    |
               |     R      |   DB   |    |
               +----------->| SLAVE1 |<---+      
                            |        |    
                            `--------`    

What is the ideal network configuration for this setup.

1) Should I use multiple NICs on the postgres server, so that service and replication can be setup on different networks ?

2) If I use multiple NICs, will PGpool be able to detect the service state and replication state reliably ?

What are the network configuration best practices, in this scenario ?

Thanks for your help.