||Manages a zone (collection of H.323 devices).
Required Functionality: Address translation, admissions
control, bandwidth control.
Optional Functionality: Call authorization, bandwidth management,
supplementary services, directory services, call management
||Provides interoperability between different
networks, converts signalling and media e.g., IP/PSTN gateway.
||Endpoint on a LAN. Supports real-time, 2-way
communications with another H.323 entity. Must support voice
(audio codecs) and signalling (Q.931, H.245, RAS). Optionally
supports video and data e.g., PC phone or videophone, Ethernet
||Supports conferences between 3 or more endpoints.
Contains multi-point controller (MC) for signalling. May
contain multi-point processor (MP) for media stream processing.
Can be stand-alone (i.e., PC) or integrated into a gateway,
gatekeeper or terminal.