Cloudee, think about it. How are you going to find out if you are the only one in the sky? By looking around? Of course not. You establish the presence of others by making the 4 AIP calls (2 inbound, 2 outbound) and getting responses. That's it. Then, if a conflict exists, you make extra calls to resolve that conflict. That's it. This isn't hard.
Leadbalon, you're on my Ignore list, remember?