H.323
""?
, VoIP H.323.
H.323 ITU-T (International Telecommunication Union - Telecommunications) 1996 , LAN (Local Area Network). , IP , WAN (Wide Are Network) .
H.323 , , , - - .
H.323
G.xxx/RTP/UDP/IP H.xx/RTP/UDP/IP, RTCP.
H.255 RAS (Registration, Admission, Status) .
H.245 , .
IP H.255.0, , Q.931, ISDN.
H.323 - :
-
H.323, - . , H.323, IP . IP , .
- (Gateway)
, H.323 , ISDN (Integrated Services Digital Network) PSTN (Public Switched Telephone Network). , H.323 (3G), H.324.
- (Gatekeeper)
, H.323. : , , , .
: direct routed gatekeeper routed
direct routed, (), RAS IP .
gatekeeper routed , .
, (zone), .
- (Multipoint Control Unit)
, - - H.323 . , - -, - -.
, , , . , H.323 , , .

H.323, . , Q.931, H.323, ISDN.