Dynamic H.245 Stage for Incoming Calls
When a call comes in on an H.323 interface that you have configured for dynamic H.245 stage support.
The Oracle® Enterprise Session Border Controller includes its H.245 address in the h245Address field of the first H.225/Q.931 message. The Oracle® Enterprise Session Border Controller does this after it receives the first H.225/Q.931 message with an H.245 address in the outgoing call. Based on the first H.225/Q.931 message received by the Oracle® Enterprise Session Border Controller that has an H.245 address, the Oracle® Enterprise Session Border Controller selects the message in which to include the H.245 address as outlined in the table below.
| Message Received with H.245 Address | Message Sent with H.245 Address |
|---|---|
| Call Proceeding | Call Proceeding, Progress, Alerting, Connect or Facility.
The H.245 address is sent in the Call Proceeding message if the system has not sent a Call Proceeding message in the incoming call. This is true only when you enable the Fast Start in first message parameter for the incoming stack; this parameter establishes whether or not Fast Start information must be sent in the first response to a Setup message. Otherwise, the message in which the H.245 address is sent depends on what message is received after the Call Proceeding message. This is because the Oracle® Enterprise Session Border Controller sends its Call Proceeding message directly after receiving the Setup message. |
| Progress | Progress |
| Alerting | Alerting |
| Connect | Connect |
| Facility | Facility |
When it receives the first H.225/Q.931 message with an H.245 address in the outgoing call, the Oracle® Enterprise Session Border Controller creates a listening socket on the incoming interface. It also includes the socket address and port in the H.245 address of the next H.225/Q.931 message that it sends. If there is no pending H.225/Q.931 message for the Oracle® Enterprise Session Border Controller to send, it instead sends a Facility message with the reason startH245. Then the H.245 channel is established when a TCP connection is made to the listening socket.
For the outgoing leg of a call that came in on the H.323 stack configured for H.245 dynamic stage support, the Oracle® Enterprise Session Border Controller starts establishing the H.245 channel when it receives the first H.225/Q.931 message with H.245 address information. It also starts to establish a TCP connection to the address and port specified in the H.245 address information. The H.245 channel for the outgoing call is established while the H.245 address (h245Address) is sent in the incoming call as described above.
