Outlook integration with NAV 5.0

Our company is deciding whether to go with a 3rd party hosting service for MS Exchange, but we have a concern how this will affect the integration with Nav 5.0 and Outlook on user computers? Is the integration with NAV 5.0 and Outlook client or server side?

If we decide to have Exchange hosted, will end users still be able to run Segments from NAV without issue?