Here are a few pointers if you find yourself planning security for a conference of your own.
1. Stanchions and barriers can be your best friend. Create a barrier between you, the speaker, and the crowd. This allows for free movement of all VIP's and creates a buffer zone between you and the masses.
2. Research a second entrance that the speakers can use that will keep them from having to walk through the crowds to get to their seat or the stage. Most buildings have fire exits, back doors, service doors, ect. You may need to become creative.
3. Have a restroom and plan identifies if the speakers needs to visit the facilities. Is there a restroom that they can use that is separate from the rest of the group.
4. Determine a location that the speaker can hold prior to speaking or for immediately after he is done. It is easier to move him from one location to the next when some of the crowd has dissipated.
5. If you have a security team integrate your plan into the plan of the ushers or greeters. The can act as a force multiplier for you and assist you with many of your needs.