A. Although my immediate impulse is to say "get a less flaky satellite connection," that probably won’t help much. Satellite channels have lots of latency because all signals must travel to geosynchronous Earth orbit (GEO) and back again—a round trip that takes at least 0.25 seconds. That amount of latency is too much for the site connector, and you’ll probably need to make some adjustments to your servers’ TCP/IP parameters to allow for the increased latency. (In fact, the Internet Engineering Task Force—IETF—is working on a TCP/IP variant that can be used to communicate with interplanetary spacecraft!)
Given the fact that you’re probably stuck with your satellite connection, the X.400 connector is probably your best choice for connecting the servers because X.400 works well on connections with lots of latency or high error rates. As a bonus, you can schedule X.400 connectors to take advantage of off-peak rates. In general, after you get an X.400 connector configured, you can leave it alone—they tend to be very robust in day-to-day operation. However, you must have the Enterprise Edition of Exchange Server to get X.400 connectors, so you might be facing a substantial upgrade cost.