Web service Scenario

Dear Experts,

I have 2 scenarios for Process integration wherein I have to consume 2 web services.

One is on a system which is in our landscape and the other one is outside the landscape.

I wanted to know how different would the configurations be for these two scenarios? Would there be a party involved in scenario 1 or 2? Would there be a difference the way the SOAP receiver adapter is configured?

How many SLD entries would I need?

Any help would be appreciated..

Thanks, Rolmen