Onno W. Purbo Onno@indo.net.id H.323 Onno W. Purbo Onno@indo.net.id

References Dr. Andreas Steffen, Komunikationsysteme

ITU-T H.323

ITU-T Multimedia Comm

H.323 Network Components

H.323 Gateways Functions .. Physical Interface LAN  PSTN Call setup POTS (analog) ISDN (digital) Call setup Setup & release call both LAN & PSTN Translation of Transmission Multiplex Formats H.225.0 to H.221 / H.223

H.323 Gateways Functions .. Translation of System Control Protocol H.245 to H.242 Audio / Video Transcoding Translation among audio codecs, conversion to analog voice. Translation among video codecs (if terminal do not support negotiation)

H.323 gatekeepers

Registration, Admission and Status ..

Registration, Admission and Status (RAS) RAS defined in ITU-T H.225.0 RAS is used between H.323 endpoint and the gatekeeper of H.323 zone they are assigned to.

Automatic Gatekeeper Discovery

Endpoint Registration

Endpoint Unregistration

Endpoint Location

Endpoint Admission To Network

H.323 Gatekeeper Functionality Address Registration & Translation RRQ/RCF/RRJ and LRQ/LCF/LRJ messages. Translation of alias addresses to transport addresses. Admission Control ARQ/ACF/ARJ messages. Authorization of LAN access (call authorization, bandwidth). Bandwidth Control and Management BRQ/BCF/BRJ messages. Dynamic change of requested and available bandwidth.

H.323 call setup & control