ESS in NWBC or ESS in SAP-Portal

Dear experts.

I am begin with the configuration for ESS & MSS and I have the following doubt:

1. What roles should I use if use ESS in NWBC?

2. What roles should I use if use ESS in SAP Portal?

With this two option , What is the better option for work ESS? And who should define what option use (Basis)?

Thanks in advance

Regards