RFC to WS with HTTPS

Hi guys, we are working on SAP PI 7.1, and we have the following requirement with RFC to WS scenario.

The department WS generated the service, it has an input parameter of type byte array and returns a byte array type, internally the service encrypts the message.

We need to discuss how to proceed suggestions from PI with the following:

1.Invoking WS with HTTPS

2. Invoking WS with integrated security, which involves sending credentials of a domain user.

3. Invoking WS with byte array as input and output. And maximum supported size.

4. Form publication for SAP

We appreciate the help we can provide.

Regards.