XI vs Connectors (Like JCo and .NET)

Hi All,

I'm delving into the integration - interoperability aspects of SAP and to be honest I'm getting confused by the 'sales' pitches on the nicely looking presentations.

Clearly XI is seperated from the connectors like JCo and .NET as they operate on the different levels of the 'Netweaver' Model: the former on the Process Integration layer the later on the Application Platform layer.

So there have to be a difference somewhere but I can see it. For me they are doing more or less the same thing ie connecting SAP with third party applications.

So why make a distinction?

And when to use what?

Can someone explain this to me or divert me to a site where I can get clear explanation.

Many thanks in advance and best regards,

BV