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Call Flows

Purpose

The following diagrams depict some of the basic H.323 call flows. They are examples and not necessarily functional call flows. Refer to Appendix C, H.323 Call Flows and Message Traces for call flows that include the message traces.

H.323 Incoming Call - Fast Connect, No Gatekeeper

H.323 Incoming Call - Fast Connect, Gatekeeper

H.323 Outgoing Call - Fast Connect, No Gatekeeper

H.323 Incoming - Fast Connect, Gatekeeper

H.323 Incoming Call with H.245 Procedure

H.323 Outgoing Call with H.245 Procedure

User Input Indication for Pre-Paid Applications

H.323 Endpoint supports DTMF - Digits received from PSTN side

H.323 Endpoint supports DTMF - UII received from IP side

H.323 Endpoint supports only Alphanumeric - Digits received from the PSTN side

H323 Endpoint supports only Alphanumeric - Digits are received from IP side

Call Release Call Flows

Host Initiated Call Release

Network Initiated Call Release

ITU-T standard defines a set of call control, channel setup, and codec specifications for transmitting real-time voice and video over networks that do not offer guaranteed service or quality of service.
An H.323 entity on the network that provides address translation and controls access to the network for H.323 terminals and other end points. The gatekeeper may also provide other services to the endpoints such as bandwidth management and locating gateways.
An H.323 terminal or gateway, or MCU. An endpoint can call and be called. It generates and/or terminates the information stream.
Public Switched Telephone Network
Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
A computer, attached to the Excel platform through an RS-232 or Ethernet link, from which you run the telecommunications application that controls the Excel platform.