The gatekeeper is the focal point of the H.323 multimedia network. The H.323 standard is implemented in production networks through zones.
Zones are the set of endpoints over which one and only one gatekeeper has jurisdiction.
Regardless of the physical location of the gatekeeper program code, there must be only one active runtime gatekeeper per zone. The Gatekeeper Environment A gatekeeper manages all zone activities. This endpoint discovery and registration process is a prerequisite for gatekeeper zone management. The choice of gatekeeper is critical to the optimal operation of a total H.323 solution. The gatekeeper allows developers the ability to scale up the system to a large number of users while taking care of interzone call routing.