Function description
- The 28181 protocol does not support public network intercom. The document introduces two docking methods to realize the dialogue between 28181 equipment and the platform using public network.
- The platform calls to the device through broadcasting, and then the platform opens the real- time audio and video of the device to listen to the sound of the device and realize two- way dialogue
First way:
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According to the national standard protocol, the server sends an audio (excluding video) request to the device, and invite sdp fills in the ip and port number of the server, but this only opens the audio of the device;
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The national standard realizes intercom. After the first step, it is necessary to send a broadcast request to the device. The device actively sends invite and opens the audio of the client.
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After receiving the broadcast request, the device will send invite to open the client audio, and the server will reply with ip and port number. After the whole dialog is successfully established
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The device will send three rtp empty packets to the ip and port number specified by the server. At this time, the server will obtain the ip and port number of the device and can push the audio stream.
Note: The attachment in the upper right corner shows an example of data capture. **
Note: If the device does not support the audio (without video) request in the first step, only the audio and video (with video) request is supported. After the manufacturer type in the device information is changed to HB, the audio and video request will be sent to the device in the first step. It is equivalent to requesting equipment video during intercom, which will increase broadband occupation. **
Second way:
On the basis of the first method, the process of the fourth step is optimized. The manufacturer type needs to be selected as BA in the equipment management on the platform.
**Note: The program intercom will also request video, will take up more broadband. **
1. According to the national standard protocol, the invite sdp sent by the server to the device fills in the ip and port number of the server, but this only opens the audio and video of the device;
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The national standard realizes intercom. After the first step, it is necessary to send a broadcast request to the device. The device actively sends invite and opens the audio of the client.
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After receiving the broadcast request, the device will send invite to open the client audio, and the server will reply with ip and port number. After the whole dialog is successfully established
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After the signaling interaction is completed, the device actively sends tcp connection handshake to push the audio stream
Precautions
Supplement: Non- broadcast (audio and video), manufacturer type YW(9)
