Trying to implement TDE for 12.1.0.2 2-node RAC with Standby database. My questions are:

Environment:

12.1.0.2 2-node RAC database with a physical standby.

Note: We don't intend on doing role-switch (standby first) approach and can afford downtime. I have been following below doc:

http://www.oracle.com/technetwork/database/availability/tde-conversion-dg-3045460.pdf

1. If we want to avoid the 'Role Switch', can we still Encrypt tablespaces using Standby first, and then Primary?

2. How long in duration can we leave the STANDBY tablespaces encrypted and PRIMARY not.

3. Any other complications that we can expect?

4. Can we store Wallet in ASM Disk Group for a RAC environment?

5. Can we use the same encryption keys/wallet for RMAN backups?