ECC and Ariba Sourcing Integration

Hi,

I work for a customer that's willing to use Ariba Sourcing with ECC integration, the scenario where you create an RFQ in ECC and it goes to Ariba to continue the sourcing process.

My question is, how is this integration achieved? Is it done via PI, or with the Ariba Network Adapter, or both? Do we need help from Ariba team to get this done or can it be done from customer side?

Thanks