Universal events

Universal events are required for all RTMS implementations. They handle the connection handshake protocol, keep-alive operations, session and stream state management, and media data delivery.

Use these events with the product-specific events for your implementation. For Meetings, Webinars, or Video SDK, see Session events. For Contact Center, see Contact Center events.

Message transmission channels

RTMS events are transmitted through two connection types established during the handshake process.

Signaling connection	Media connection
SIGNALING_HAND_SHAKE_REQ``SIGNALING_HAND_SHAKE_RESP``DATA_HAND_SHAKE_REQ``DATA_HAND_SHAKE_RESP``EVENT_SUBSCRIPTION``EVENT_UPDATE``CLIENT_READY_ACK``STREAM_STATE_UPDATE``SESSION_STATE_UPDATE``SESSION_STATE_REQ``SESSION_STATE_RESP``KEEP_ALIVE_REQ``KEEP_ALIVE_RESP``STREAM_STATE_REQ``STREAM_STATE_RESP``STREAM_CLOSE_REQ``STREAM_CLOSE_RESP``VIDEO_SUBSCRIPTION_REQ``VIDEO_SUBSCRIPTION_RESP	KEEP_ALIVE_RESP``MEDIA_DATA_AUDIO``MEDIA_DATA_VIDEO``MEDIA_DATA_SHARE``MEDIA_DATA_TRANSCRIPT``MEDIA_DATA_CHAT

The examples on this page use meeting-specific values (such as meeting_uuid and meeting.rtms_started), but the message structure is the same across all RTMS-supported products.

Signaling handshake request

Sent to the signaling connection

Send a signed handshake request to the server_urls provided in the meeting.rtms_started event, also known as the signaling connection. Use your app credentials with the session details to generate the signature. For more information, see App establishes signaling connection.

Use meeting.rtms_started and meeting.rtms_stopped events in the Webhook reference to get initial session details like the meeting_uuid and rtms_stream_id.

{
    "msg_type": 1,
    "protocol_version": 1,
    "sequence": 1,
    "meeting_uuid": "xxxxxxxxxx",
    "rtms_stream_id": "xxxxxxxxxx",
    "signature": "xxxxxxxxxx",
    "buffer_data": false
}

Field	Type	Description
`msg_type`	int	The request from the app to the RTMS server to initiate a handshake. For more information, see RTMS_MESSAGE_TYPE.
`protocol_version`	int	The RTMS design version. By default, it's `1.0`.
`sequence`	int	The sequence number of the message. Must start at `1`.
`meeting_uuid`	string	The unique identifier for the session.
`rtms_stream_id`	string	The unique identifier of the RTMS stream. Multiple streams are possible for a session if streaming access stops or restarts.
`signature`	string	The authentication signature created using app credentials and session details.
`buffer_data`	bool	Optional. Default is `true`. When set to `false`, any audio data captured between the time the `rtms_started` webhook event is received and the time the signaling connection is established will be dropped.
> When `buffer_data` is set to `false`, only the initial buffer data is dropped. Audio data will continue to be buffered during connection interruptions, and any buffered data will be transmitted once a new connection is established.

Signaling handshake response

Sent from the signaling connection

The signaling connection will respond with a signaling handshake response that includes the URLs of the media connections.

{
    "msg_type": 2,
    "protocol_version": 1,
    "sequence": 0,
    "status_code": 0,
    "reason": "",
    "media_server": {
        "server_urls": {
            "audio": "wss://127.0.0.0:443",
            "video": "wss://127.0.0.0:443",
            "transcript": "wss://127.0.0.0:443",
            "all": "wss://127.0.0.0:443"
        }
    }
}

Field	Type	Description
`msg_type`	int	The response from the signaling connection to the app after a handshake attempt. For more information, see RTMS_MESSAGE_TYPE.
`protocol_version`	int	The RTMS design version. By default, it's `1.0`.
`sequence`	int	The sequence number of the message.
`status_code`	int	The status code of the message. Status `0` means success. For more information, see RTMS_STATUS_CODE.
`reason`	string	This is empty if successful. If failed, it will contain the reason for the failure.
`media_server`	object	The media connection information.
`server_urls`	object	Locations of available media connections. The response will depend on the app's available scopes. For example, if the app only supports audio, only `audio` will be included.

Media handshake request

Sent to the media connection

To establish a connection, send a handshake request to the media connections of the RTMS server(s) that were included in the signaling handshake and include the associated media parameters. The media connection responds with confirmed parameters of the requested media types.

Apps can request all available media streams or specify media streams by content type. If all are requested, the signaling connection responds with all media connections available according to the app's requested scopes.

If the app has scopes for audio and transcript only, a request for all media will include audio and transcript data but not video, chat, or screen share data.

To request only one media type, specify that media type in the media_type field. For more information, see MEDIA_DATA_TYPE. Use "media_type": 32 for all.

Media parameters (media_params) are optional. If not specified, the default values will be used.

For more information, see Data type definitions for options on codecs, resolutions, rates, etc.

{
    "msg_type": 3,
    "protocol_version": 1,
    "sequence": 0,
    "meeting_uuid": "4xxxxxxxxxx",
    "rtms_stream_id": "xxxxxxxxxx",
    "signature": "xxxxxxxxxx",
    "media_type": 32,
    "media_params": {
        "audio": {
            "content_type": 2,
            "sample_rate": 1,
            "channel": 1,
            "codec": 1,
            "data_opt": 1,
            "send_rate": 100
        },
        "video": {
            "codec": 5,
            "resolution": 2,
            "fps": 5
        },
        "deskshare": {
            "codec": 5,
            "resolution": 3,
            "fps": 1
        },
        "transcript": {
            "content_type": 5,
            "src_language": 9,
            "enable_lid": true
        }
    }
}

{
    "msg_type": 3,
    "protocol_version": 1,
    "sequence": 0,
    "meeting_uuid": "4nYtdqLVTVqGJ+QB62ED7Q==",
    "rtms_stream_id": "03db704592624398931a588dd78200cb",
    "signature": "kDBZVzEWgox9tWVBc7DHsjW2OnVD/6H1zN2vdmU9VY8=",
    "media_type": 1,
    "media_params": {
        "audio": {
            "content_type": 2,
            "sample_rate": 1,
            "channel": 1,
            "codec": 1,
            "data_opt": 1,
            "send_rate": 20
        }
    }
}

{
    "msg_type": 3,
    "protocol_version": 1,
    "sequence": 0,
    "meeting_uuid": "4nYtdqLVTVqGJ+QB62ED7Q==",
    "rtms_stream_id": "03db704592624398931a588dd78200cb",
    "signature": "kDBZVzEWgox9tWVBc7DHsjW2OnVD/6H1zN2vdmU9VY8=",
    "media_type": 2,
    "media_params": {
        "video": {
            "codec": 5,
            "resolution": 2,
            "fps": 5
        }
    }
}

{
    "msg_type": 3,
    "protocol_version": 1,
    "sequence": 0,
    "meeting_uuid": "4nYtdqLVTVqGJ+QB62ED7Q==",
    "rtms_stream_id": "03db704592624398931a588dd78200cb",
    "signature": "kDBZVzEWgox9tWVBc7DHsjW2OnVD/6H1zN2vdmU9VY8=",
    "media_type": 4,
    "media_params": {
        "deskshare": {
            "codec": 5,
            "resolution": 3,
            "fps": 1
        }
    }
}

{
    "msg_type": 3,
    "protocol_version": 1,
    "sequence": 0,
    "meeting_uuid": "4nYtdqLVTVqGJ+QB62ED7Q==",
    "rtms_stream_id": "03db704592624398931a588dd78200cb",
    "signature": "kDBZVzEWgox9tWVBc7DHsjW2OnVD/6H1zN2vdmU9VY8=",
    "media_type": 8,
    "media_params": {
        "transcript": {
            "content_type": 5,
            "src_language": 9,
            "enable_lid": true
        }
    }
}

{
    "msg_type": 3,
    "protocol_version": 1,
    "sequence": 0,
    "meeting_uuid": "4nYtdqLVTVqGJ+QB62ED7Q==",
    "rtms_stream_id": "03db704592624398931a588dd78200cb",
    "signature": "kDBZVzEWgox9tWVBc7DHsjW2OnVD/6H1zN2vdmU9VY8=",
    "media_type": 16
}

Field	Type	Description
`msg_type`	int	The app sends this message to the media connection to request a connection with the specified media parameters. For more information, see RTMS_MESSAGE_TYPE.
`protocol_version`	int	The RTMS design version. By default, it's `1.0`.
`sequence`	int	The sequence number of the message.
`meeting_uuid`	string	The unique identifier for the session.
`rtms_stream_id`	string	The unique identifier of the RTMS stream. Multiple streams are possible for a session if streaming access stops or restarts.
`signature`	string	The authentication signature created using app credentials and session details.
`media_type`	int	The media type of the stream, either audio (1), video (2), screen share (4), transcript (8), chat (16), or all (32). For more information, see MEDIA_DATA_TYPE.
`media_params` (Optional)	object	The media parameters of the stream that define the media formats. Parameters are set to default if not specified and returned in the response.
`content_type`	int	The content type of the media stream, either RTP (1), raw audio (2), raw video (3), file stream (4), or text (5). For more information, see MEDIA_CONTENT_TYPE.
`sample_rate` (audio)	int	The sample rate of the audio stream. For more information, see AUDIO_SAMPLE_RATE.
`channel` (audio)	int	The channel of the audio stream, either mono (1) or stereo (2). For more information, see AUDIO_CHANNEL.
`codec` (audio)	int	The codec of the audio data. Can be L16 (1), G711 (2), G722 (3), or Opus (4). For more information, see MEDIA_PAYLOAD_TYPE.
`data_opt` (audio)	int	Defines whether media is separated or merged. For example, mixed audio or separated audio streams. For more information, see MEDIA_DATA_OPTION.
`send_rate` (audio)	int	The send rate of the audio stream in milliseconds (ms). Must be a multiple of 20, up to 1000 ms.
`codec` (video)	int	The codec of the video data that is set during the handshake and doesn't change during the session. Can be JPG or PNG when `fps` {'<='} 5 and H.264 when `fps` > 5. The default is JPG with an `fps` of 5.If the handshake request sets the `fps` > 5 but doesn't specify a `codec`, the server will set the `codec` to JPG (default) and the `fps` to 5. For more information, see MEDIA_PAYLOAD_TYPE.
`codec` (screen share)	int	The codec of the screen share data that is set during the handshake and doesn't change during the session. Can be JPG or PNG when `fps` {'<='} 1 and H.264 when `fps` > 1. The default is JPG with an `fps` of 1.If the handshake request sets the `fps` > 1 but doesn't specify a `codec`, the server will set the `codec` to JPG (default) and the `fps` to 1. For more information, see MEDIA_PAYLOAD_TYPE.
`resolution` (video)	int	The resolution of the video stream. Can be SD (1), HD (2), FHD (3), or QHD (4). The default is HD. For more information, see MEDIA_RESOLUTION.
`resolution` (screen share)	int	The resolution of the screen share stream. Can be SD (1), HD (2), FHD (3), or QHD (4). The default is FHD. For more information, see MEDIA_RESOLUTION.
`fps` (video & screen share)	int	The frames per second of the video stream. Maximum of 30.
`src_language`	int	Optional. The language of the transcript. If not specified, English will be the default language for the first 30 seconds of transcription. If specified, RTMS will transcribe the first 30 seconds of audio based on this language setting. For more information, see RTMS_TRANSCRIPT_LANGUAGE.
> After 30 seconds, the audio language will be automatically detected and override this parameter.
`enable_lid`	bool	Optional. Default is true and Language Identification is enabled. When set to false, Language Identification is disabled and transcription will rely solely on the `src_language` parameter.

Media handshake response

Sent from the media connection

The media connection will respond with with a media handshake response that includes information about the media connections.

{
    "msg_type": 4,
    "protocol_version": 1,
    "status_code": 0,
    "reason": "",
    "sequence": 0,
    "payload_encrypted": true,
    "media_params": {
        "audio": {
            "content_type": 2,
            "sample_rate": 1,
            "channel": 1,
            "codec": 1,
            "data_opt": 1,
            "send_rate": 100
        },
        "video": {
            "content_type": 3,
            "codec": 5,
            "resolution": 2,
            "data_opt": 3,
            "fps": 5
        },
        "deskshare": {
            "content_type": 3,
            "codec": 5,
            "resolution": 3,
            "fps": 1
        },
        "transcript": {
            "content_type": 5,
            "src_language": 9,
            "enable_lid": true
        },
        "chat": {
            "content_type": 5
        }
    }
}

{
    "msg_type": 4,
    "protocol_version": 1,
    "status_code": 0,
    "reason": "",
    "sequence": 0,
    "payload_encrypted": true,
    "media_params": {
        "audio": {
            "content_type": 2,
            "sample_rate": 1,
            "channel": 1,
            "codec": 1,
            "data_opt": 1,
            "send_rate": 100
        }
    }
}

{
    "msg_type": 4,
    "protocol_version": 1,
    "status_code": 0,
    "reason": "",
    "sequence": 0,
    "payload_encrypted": true,
    "media_params": {
        "video": {
            "content_type": 3,
            "codec": 5,
            "resolution": 2,
            "data_opt": 3,
            "fps": 5
        }
    }
}

{
    "msg_type": 4,
    "protocol_version": 1,
    "status_code": 0,
    "reason": "",
    "sequence": 0,
    "payload_encrypted": true,
    "media_params": {
        "deskshare": {
            "content_type": 3,
            "codec": 5,
            "resolution": 3,
            "fps": 1
        }
    }
}

{
    "msg_type": 4,
    "protocol_version": 1,
    "status_code": 0,
    "reason": "",
    "sequence": 0,
    "payload_encrypted": true,
    "media_params": {
        "transcript": {
            "content_type": 5,
            "src_language": 9,
            "enable_lid": true
        }
    }
}

{
    "msg_type": 4,
    "protocol_version": 1,
    "status_code": 0,
    "reason": "",
    "sequence": 0,
    "payload_encrypted": true,
    "media_params": {
        "chat": {
            "content_type": 5
        }
    }
}

Field	Type	Description
`msg_type`	int	The response from the media connection to the app after a handshake attempt. For more information, see RTMS_MESSAGE_TYPE.
`protocol_version`	int	The RTMS design version. By default, it's `1.0`.
`status_code`	int	The status code of the message. Status `0` means success. For more information, see RTMS_STATUS_CODE.
`reason`	string	This is empty if successful. If failed, it will contain the reason for the failure.
`sequence`	int	The sequence number of the message.
`payload_encryption` (Optional)	bool	Default is false for any TLS connection. The encryption keys in the signaling handshake response message. If true, the payload is encrypted. If false, but the payload protocol is UPD, and the payload will still be encrypted.
`content_type`	int	The content type of the media. For more information, see MEDIA_CONTENT_TYPE.
`sample_rate`	int	The sample rate of the audio stream. For more information, see AUDIO_SAMPLE_RATE.
`channel`	int	The channel of the audio stream, either mono (1) or stereo (2). For more information, see AUDIO_CHANNEL.
`codec`	int	The codec of the audio data. Can be L16 (1), G711 (2), G722 (3), or Opus (4). For more information, see MEDIA_PAYLOAD_TYPE.
`data_opt`	int	Defines whether media is separated or merged. For example, mixed audio or separated audio streams. For more information, see MEDIA_DATA_OPTION.
`send_rate`	int	The send rate of the audio stream in milliseconds (ms). Must be a multiple of 20. Can be up to 1000 ms.
`codec` (video)	int	The codec of the video data that is set during the handshake and doesn't change during the session. Can be JPG or PNG when `fps` {'<='} 5 and H.264 when `fps` > 5. The default is JPG with an `fps` of 5.If the handshake request sets the `fps` > 5 but doesn't specify a `codec`, the server will set the `codec` to JPG (default) and the `fps` to 5. For more information, see MEDIA_PAYLOAD_TYPE.
`codec` (screen share)	int	The codec of the screen share data that is set during the handshake and doesn't change during the session. Can be JPG or PNG when `fps` {'<='} 1 and H.264 when `fps` > 1. The default is JPG with an `fps` of 1.If the handshake request sets the `fps` > 1 but doesn't specify a `codec`, the server will set the `codec` to JPG (default) and the `fps` to 1. For more information, see MEDIA_PAYLOAD_TYPE.
`resolution` (video)	int	The resolution of the video stream. Can be SD (1), HD (2), FHD (3), or QHD (4). The default is HD. For more information, see MEDIA_RESOLUTION.
`resolution` (screen share)	int	The resolution of the screen share stream. Can be SD (1), HD (2), FHD (3), or QHD (4). The default is FHD. For more information, see MEDIA_RESOLUTION.
`fps` (video & screen share)	int	The frames per second of the video stream. Maximum of 30.
`src_language`	int	Optional. The language of the transcript. If not specified, English will be the default language for the first 30 seconds of transcription. If specified, RTMS will transcribe the first 30 seconds of audio based on this language setting. For more information, see RTMS_TRANSCRIPT_LANGUAGE.
> After 30 seconds, the audio language will be automatically detected and override this parameter.
`enable_lid`	bool	Optional. Default is true and Language Identification is enabled. When set to false, Language Identification is disabled and transcription will rely solely on the `src_language` parameter.

Client ready ACK message

Sent to the signaling connection

After the app receives the data handshake response from the media connection, it needs to send a client ready ack to the signaling connection to indicate that the full handshake has completed and that it is ready to receive media data.

This message should be sent after the signaling and media connections have been established.

{
    "msg_type": 7,
    "rtms_stream_id": "xxxxxxxxxx"
}

Field	Type	Description
`msg_type`	int	The app sends this message to the signaling connection to acknowledge that the server is ready to receive media. For more information, see RTMS_MESSAGE_TYPE.
`rtms_stream_id`	string	The unique identifier for the RTMS stream.

Keep-alive request

Sent from the media connection

To maintain stable connections and prevent timeouts, RTMS servers send a keep-alive request to both the signaling and media connections every 10 seconds.

When three keep-alive requests are unanswered, the RTMS server takes different actions for the different connection types.

Signaling connection - The RTMS server will interrupt both the signaling and media connections, wait for one minute to allow for reconnection, and, if the connection is not restored, it will end the RTMS stream.
Media connections - The RTMS server will interrupt the media connection, wait for 65 seconds to allow for reconnection, and, if the connection is not restored, it will end the RTMS stream.

If an app doesn't receive a keep-alive request for 65 seconds, we recommend that the app reestablish the connection by resending the signaling handshake request. For more information, see Working with streams.

The RTMS server sends the following request to confirm the app wants to maintain a connection.

{
    "msg_type": 12,
    "timestamp": 1727384349123
}

Field	Type	Description
`msg_type`	int	The media connection sends this message to confirm the app wants to maintain a connection. For more information, see RTMS_MESSAGE_TYPE.
`timestamp`	unsigned long	The Unix timestamp of the request.

Keep-alive response

Sent to the media connection

To maintain the connection, an app should respond to the request with the following response. The timestamp in the response must match the request.

{
    "msg_type": 13,
    "timestamp": 1727384349123
}

Field	Type	Description
`msg_type`	int	The app sends this message to the media connection to maintain a connection. For more information, see RTMS_MESSAGE_TYPE.
`timestamp`	unsigned long	The Unix timestamp of the keep-alive request.

Subscribe to events

Sent to the signaling connection

Send this message to the signaling connection to get data about behavior during sessions.

Note

Some events are sent automatically and don't need to be subscribed to. To ensure your app works as expected, don't subscribe to these events.

FIRST_PACKET_TIMESTAMP = 1

MEDIA_CONNECTION_INTERRUPTED = 7

This message does not require a response.

{
    "msg_type": 5,
    "events": [
        {
            "event_type": 2,
            "subscribe": true
        }
    ]
}

Field	Type	Description
`msg_type`	int	The app sends this message to the signaling connection to subscribe or unsubscribe to in-session events from the signaling connection. For more information, see RTMS_MESSAGE_TYPE.
`event_type`	int	The type of event to subscribe to. For more information, see RTMS_EVENT_TYPE.
`subscribe`	bool	A boolean. `True` - subscribe to events `False` - unsubscribe from events

Audio data

Sent from the media connection

Audio data from the media connection of a participant in a session. It can be either merged audio or individual audio.

{
    "msg_type": 14,
    "content": {
        "user_id": 16778240,
        "user_name": "John Smith",
        "data": "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",
        "length": 1024,
        "timestamp": 1738392033699
    }
}

{
    "msg_type": 14,
    "content": {
        "user_name": "John Smith",
        "data": "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"
    }
}

{
    "msg_type": 14,
    "content": {
        "channel_id": "c8b2d3ce-b0d6-4cd1-9195-fe17a4bd5b8e",
        "data": "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",
        "length": 1024,
        "timestamp": 1738392033699
    }
}

Field	Type	Description
`msg_type`	int	Audio data sent from the media connection. For more information, see RTMS_MESSAGE_TYPE.
`user_id`	int	The unique identifier of the participant whose audio is included in the data.
`user_name`	string	The username of the participant whose audio is included in the data. If the `user_id` in the RTP header is `0`, no `user_name` will be sent.
`channel_id`	string	For Zoom Contact Center engagements, the unique identifier of the SIP trunk channel that carries this audio. Each party in an engagement is on a separate channel, so `channel_id` identifies which side of the call this audio belongs to.
`data`	string	Audio data, base64-encoded binary.
`length`	int	The length of the original binary data before base64 encoding.
`timestamp`	unsigned long	The Unix timestamp of the data.

Video data

Sent from the media connection

Video data from the media connection of the Active speaker participant in a session.

{
    "msg_type": 15,
    "content": {
        "user_id": 16778240,
        "user_name": "John Smith",
        "data": "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",
        "length": 1024,
        "timestamp": 1738392033699
    }
}

Field	Type	Description
`msg_type`	int	Video data sent from the media connection. For more information, see RTMS_MESSAGE_TYPE.
`user_id`	int	The unique identifier of the participant whose video was included in the data.
`user_name`	string	The username of the participant whose video was included in the data.
`data`	string	Video data, base64-encoded binary.
`length`	int	The length of the original binary data before base64 encoding.
`timestamp`	unsigned long	The Unix timestamp of the data.

Screen share data

Sent from the media connection

Content shared by a participant in a session sent from the media connection.

{
    "msg_type": 16,
    "content": {
        "user_id": 16778240,
        "user_name": "John Smith",
        "data": "Hw1kDacNAA4sDkMOAQ5eDekMgAzXCw0L4Al4CDwHBAayBEwDmwHD/wn+rfyQ+3z6Z/k4+Ef3jvb09aj1YPUF9QL1OfVt9eH1f/YE96P3jPib+dX6Pvyr/ef+IABcAZ4CmQN3BFAF6QVxBs0G9wbjBqYGXwYFBm8FxwT/Aw4DHAIkARYA7v6o/T382/qq+YD4fPd99mz1p/Qq9KTzcfNv807zcPPQ8z70yfQ89az1SPbO9m/3Lfjf+I75M/rz+pT7KPzs/In9Fv7G/lP/q/8GAG4AtgBHAcABDQKtAkwDIgRQBYQGrgfyCEgKigvDDP4NFw/8D78QhBErEqoS/BL5EsYSfRLnEXARwhCMD1kO8ww8C5gJ5gfrBe8D3AGp/7P9IPyY+hL5t/dl9mv10fQ89NjzvvO78/HzbfTb9F71I/bw9vL3Kvlh+pX71/wr/m//owDCAbQCkwNoBPYEYQWxBZ0FZQUdBYkEBgRkA64CAgIdAT0AZf+T/tD93vz9+xf7B/o8+WX4pvcE90L2n/VM9d70pPSe9IL0nfTa9BX1cfXK9QP2S/a69hH3cPfx91P4w/hO+cr5XPr2+l/71/t9/AP9f/0R/p/+Pv/5/7IAWAH+AeMCAwQ7BaAG+wcmCZEKKQy8DT4PWhBXEVYSVBOgFM0VMxZSFhYW4BXTFUMVNBSzEtIQJg99Da0LogkXB40ESgJCAHj+ivyA+qn4KfcH9hr1JvRf89byq/Lt8kjzhvPy85P0n/X/9kn4lvni+kj84P1S/4wAuwHUAvcD9wS/BUwGaAZcBmcGTQb5BUkFQgQzAzkCVQEgALX+U/3N+4L6XfkU+Nj2o/WB9MTzOfO38g==",
        "length": 1024,
        "timestamp": 1738392033699
    }
}

Field	Type	Description
`msg_type`	int	Screen share data sent from the media connection. For more information, see RTMS_MESSAGE_TYPE.
`user_id`	int	The unique identifier of the participant who shared their screen.
`user_name`	string	The username of the participant who shared their screen.
`data`	string	Screen share video data, base64-encoded binary.
`length`	int	The length of the original binary data before base64 encoding.
`timestamp`	unsigned long	The Unix timestamp of the data.

Transcript data

Sent from the media connection

Transcript of the spoken audio in a session sent from the media connection. Messages will be sent separately for each participant who has spoken.

{
    "msg_type": 17,
    "content": {
        "user_id": 19778240,
        "user_name": "John Smith",
        "start_time": 1727384100000,
        "end_time": 1727384310000,
        "timestamp": 1727384349000,
        "language": 9,
        "data": "Hi, hello world!"
    }
}

{
    "msg_type": 17,
    "content": {
        "channel_id": "c8b2d3ce-b0d6-4cd1-9195-fe17a4bd5b8e",
        "start_time": 1738392033699,
        "end_time": 1738392036866,
        "timestamp": 1727384349000000,
        "language": 9,
        "data": "Hi, hello world!"
    }
}

Field	Type	Description
`msg_type`	int	Transcript data sent from the media connection. For more information, see RTMS_MESSAGE_TYPE.
`user_id`	int	The unique identifier of the participant whose transcript is included.
`user_name`	string	The username of the participant whose transcript is included.
`channel_id`	string	For Zoom Contact Center engagements, the unique identifier of the SIP trunk channel that carries this transcript. Each party in an engagement is on a separate channel, so `channel_id` identifies which side of the call this transcript belongs to.
`start_time`	unsigned long	The Unix timestamp of when the transcription started.
`end_time`	unsigned long	The Unix timestamp of when the transcription ended.
`timestamp`	unsigned long	The Unix timestamp of the data.
`language`	int	The language of the transcript data. For more information, see RTMS_TRANSCRIPT_LANGUAGE.
`data`	string	The transcript data, UTF-8 encoded string.

Chat data

Sent from the media connection

Chat data sent from the media connection. Each participant's chat data is sent in a separate message.

Note

RTMS currently delivers public, or everyone, meeting and webinar chat only (chat_session.type: 1). Other chat session types are reserved for future support and aren't delivered to clients today.

{
    "msg_type": 18,
    "content": {
        "timestamp": 1771635627032,
        "data": "Content of the message",
        "chat_session": {
            "type": 1
        },
        "operation_type": 1,
        "message_id": "1-{BAE4D8D3-629A-48E2-9C12-5442D81931BF}",
        "sender": {
            "user_id": 16778240,
            "user_name": "John Smith"
        },
        "files": [
            {
                "file_id": "bJtDzXMnS1ufL1SHarZnMA",
                "file_name": "test.txt",
                "file_size": 28
            }
        ],
        "delete_file_id_list": ["-i81TZFYSK2KUltQP-Y_TA"]
    }
}

Field	Type	Description
`msg_type`	int	Chat data sent from the media connection. For more information, see RTMS_MESSAGE_TYPE.
`timestamp`	unsigned long	The Unix timestamp of the data.
`data`	string	The message content. A UTF-8 encoded JSON object string.
`chat_session`	object	The chat session that the message belongs to.
`chat_session.type`	int	The type of chat session. RTMS currently only delivers `1` (`EVERYONE`, public chat). For more information, see RTMS_CHAT_SESSION_TYPE.
`operation_type`	int	The operation that produced this message, such as send, edit, or delete. For more information, see RTMS_CHAT_OPERATION_TYPE.
`message_id`	string	The unique identifier of the message.
`sender`	object	The participant who sent the message.
`sender.user_id`	unsigned int32	The unique identifier of the participant who sent the message.
`sender.user_name`	string	The username of the participant who sent the message.
`files`	array	The files attached to the message.
`files[].file_id`	string	The unique identifier of the attached file.
`files[].file_name`	string	The name of the attached file.
`files[].file_size`	unsigned long	The size of the attached file, in bytes.
`delete_file_id_list`	array	Optional. The identifiers of files removed while editing a chat message. Only present when files are removed during an edit.

Session state updated

Sent from the signaling connection

The signaling connection sends session state updated events when a new session is added or the state of a session is changed. A session can stop and resume during a stream. This message does not require a response from the app.

The STARTED state means a brand-new session has started. Record the session information locally since the state of each session is changed separately.

{
    "msg_type": 9,
    "state": 1,
    "stop_reason": 1,
    "timestamp": 1727384349123,
    "rtms_session_id": "xxxxxxxxxx"
}

Field	Type	Description
`msg_type`	int	The signaling connection sends this message when a session has been updated. For more information, see RTMS_MESSAGE_TYPE.
`state`	int	The state of a session within a stream, including if a participant or host has started, paused, resumed or stopped a session. For more information, see RTMS_SESSION_STATE.
`reason`	int	Describes why a session status has been updated. It's only sent if session state stops. For more information, see RTMS_STOP_REASON.
`timestamp`	unsigned long	The Unix timestamp of when the session was updated.
`rtms_session_id`	string	The unique identifier for the RTMS session.

Session state request

Sent to the signaling connection

Apps send the session state request event to the signaling connection to query the current session state. The signaling connection will respond with the current session state.

{
    "msg_type": 10,
    "rtms_session_id": "xxxxxxxxxx"
}

Field	Type	Description
`msg_type`	int	The app sends this message to query the current state of the session. For more information, see RTMS_MESSAGE_TYPE.
`rtms_session_id`	string	The unique identifier for the RTMS session.

Session state response

Sent from the signaling connection

The signaling connection sends the session state response event in response to a session state request event.

{
    "msg_type": 11,
    "rtms_session_id": "xxxxxxxxxx",
    "state": 1,
    "timestamp": 1727384349123
}

Field	Type	Description
`msg_type`	int	The signaling connection sends this field as a response to the query for the state of the current session. For more information, see RTMS_MESSAGE_TYPE.
`rtms_session_id`	string	The unique identifier for the RTMS session.
`state`	int	The state of the current session. For more information, see RTMS_SESSION_STATE.
`timestamp`	unsigned long	The Unix timestamp of the request. Use this to pair requests and responses.

Stream state request

Sent to the signaling connection

Apps send the current stream state request event to the signaling server to query the current stream state. Streams can be in one of the following states: inactive, active, interrupted, terminating, terminated, paused, or resumed.

{
    "msg_type": 19,
    "rtms_stream_id": "756FF58A-6332-6ECA-E4AE-21F2ABDCB485"
}

Field	Type	Description
`msg_type`	int	The app sends this message to query the current state of the state. For more information, see RTMS_MESSAGE_TYPE.
`rtms_stream_id`	string	The unique identifier of the RTMS stream.

Stream state response

Sent from the signaling connection

The signaling connection sends the stream state response event in response to a stream state request event.

{
    "msg_type": 20,
    "state": 1,
    "rtms_stream_id": "756FF58A-6332-6ECA-E4AE-21F2ABDCB485",
    "timestamp": 1694204592
}

Field	Type	Description
`msg_type`	int	The signaling connection sends this message as a response to the query for the state of the current stream. For more information, see RTMS_MESSAGE_TYPE.
`state`	int	The current state of the RTMS stream. For more information, see RTMS_STREAM_STATE.
`rtms_stream_id`	string	The unique identifier for the RTMS stream.
`timestamp`	unsigned long	The Unix timestamp of the request. Use this to pair requests and responses.

Stream state updated

Sent from the signaling connection

{
    "msg_type": 8,
    "state": 1,
    "reason": 1,
    "timestamp": 1727384349123
}

Field	Type	Description
`msg_type`	int	The signaling connection sends this message when a stream has been updated. For more information, see RTMS_MESSAGE_TYPE.
`state`	int	The state of a stream, including if a stream is active, experiencing connection issues, or needs to be terminated. For more information, see RTMS_STREAM_STATE.
`reason`	int	Describes why a stream status has been updated. For more information, see RTMS_STOP_REASON.
`timestamp`	unsigned long	The Unix timestamp of when the stream was updated.

Stream close request

Sent to the signaling connection

To gracefully close a stream from the app backend, send a STREAM_CLOSE_REQ message through the signaling connection. RTMS will respond with a STREAM_CLOSE_RESP message and terminate the stream.

{
    "msg_type": 21,
    "rtms_stream_id": "xxxxxxxxxx"
}

Field	Type	Description
`msg_type`	int	The request from the app to close the stream. For more information, see RTMS_MESSAGE_TYPE.
`rtms_stream_id`	string	The unique identifier of the RTMS stream to close.

Stream close response

Sent from the signaling connection

The signaling connection responds to a stream close request with a STREAM_CLOSE_RESP message confirming the result.

{
    "msg_type": 22,
    "rtms_stream_id": "xxxxxxxxxx",
    "status_code": 0,
    "reason": "OK",
    "timestamp": 1727384349123
}

Field	Type	Description
`msg_type`	int	The response from the signaling connection after a stream close request. For more information, see RTMS_MESSAGE_TYPE.
`rtms_stream_id`	string	The unique identifier of the RTMS stream.
`status_code`	int	The status code of the response. Status `0` means success. For more information, see RTMS_STATUS_CODE.
`reason`	string	Empty if successful. If failed, contains the reason for the failure.
`timestamp`	unsigned long	The Unix timestamp of when the response was sent.

Video subscription request

Sent to the signaling connection

To use individual video subscriptions, configure data_opt to 4 (VIDEO_SINGLE_INDIVIDUAL_STREAM) when establishing the media connection, and subscribe to PARTICIPANT_VIDEO_ON and PARTICIPANT_VIDEO_OFF events using the Subscribe to events message.

To subscribe to an individual participant's video stream, send this message through the signaling connection containing the user_id obtained from a PARTICIPANT_VIDEO_ON event. The RTMS server supports subscribing to a single individual video stream at a time, a new subscription request will automatically unsubscribe from the previous individual's stream.

{
    "msg_type": 28,
    "user_id": 16778240,
    "subscribe": true,
    "timestamp": 1738392033699
}

Field	Type	Description
`msg_type`	int	The request from the app to subscribe or unsubscribe from an individual's video stream. For more information, see RTMS_MESSAGE_TYPE.
`user_id`	unsigned int32	The unique identifier of the participant to subscribe to, obtained from a `PARTICIPANT_VIDEO_ON` event.
`subscribe`	bool	Set to `true` to subscribe, `false` to unsubscribe.
`timestamp`	unsigned long	The Unix timestamp of the request.

Video subscription response

Sent from the signaling connection

The signaling connection responds to a video subscription request. If successful, the subscribed participant's video stream will begin transmitting through the video data socket connection.

{
    "msg_type": 29,
    "user_id": 16778240,
    "status_code": 0,
    "reason": "OK",
    "timestamp": 1738392033699
}

Field	Type	Description
`msg_type`	int	The response from the signaling connection after a video subscription request. For more information, see RTMS_MESSAGE_TYPE.
`user_id`	unsigned int32	The unique identifier of the participant that was subscribed or unsubscribed.
`status_code`	int	The status code of the response. Status `0` means success. For more information, see RTMS_STATUS_CODE.
`reason`	string	Empty if successful. If failed, contains the reason for the failure.
`timestamp`	unsigned long	The Unix timestamp of the response.