I would like to understand the use case here.
Choice of edge and origin can be on per connection-application basis.
You may make a net connection:
and another net connection as
Here you have two origins.. with same edge. But they are running independent application logic.
Ohh.. I was talking about the "explicit" configuration, where your NetConnection URL can tell which origin to connect. You just need to configure your server as edge, thats it..
However, "implicit" way too should be possible. But I am not sure..
Read more about configuring edge server at http://help.adobe.com/en_US/FlashMediaServer/3.5_AdminGuide/WS5b3ccc516d4fbf351e63e3d119f2 925d1a-7ffd.html#WS5b3ccc516d4fbf351e63e3d119f2926bcf-7fff