Sends a request to a specified device and synchronously receives a response from the device.


  • Each Alibaba Cloud account can run a maximum of 1000 queries per second (QPS).
  • If the device does not sends a response within 5 seconds, IoT Platform determines a message sending failure even if the device receives the message.
Note RAM users of an Alibaba Cloud account share the quota of the account.


OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer. OpenAPI Explorer dynamically generates the sample code of the operation for different SDKs.

Request parameters

Parameter Type Required Example Description
Action String Yes RRpc

The operation that you want to perform. Set the value to RRpc.

DeviceName String Yes device1

The name of the device that receives the request.

ProductKey String Yes aldfeSe****

The ProductKey of the product to which the device belongs.

RequestBase64Byte String Yes dGhpcyBpcyBhbiBleGFtcGxl

The string that is obtained by performing Base64 encoding on the message. Example: dGhpcyBpcyBhbiBleGFtcGxl.

Timeout Integer Yes 1000

The timeout period of a response. Unit: milliseconds. Valid values: 1000 to 8000.

IotInstanceId String No iot_instc_pu****_c*-v64********

The ID of the instance. This parameter is not required for the public instance but required for Enterprise Edition instances.

Topic String No /a1uZfYb****/A_Vol****/user/update

The custom revert-RPC (RRPC) topic. To use a custom RRPC topic, you must develop the device. For more information, see Use custom topics.

If you do not specify this parameter, the default RRPC topic is used.

In addition to the preceding operation-specific request parameters, you must specify common request parameters when you call this operation. For more information about common request parameters, see Common parameters.

Response parameters

Parameter Type Example Description
Code String iot.system.SystemException

The error code returned if the call fails. For more information, see Error codes.

ErrorMessage String A system exception occurred.

The error message returned if the call fails.

MessageId Long 889455942124347392

The ID of the message. The message ID is generated by IoT Platform after the request is sent.

PayloadBase64Byte String d29ybGQgaGVsbG8=

The Base64 encoded payload that is returned by the device.

RequestId String 41C4265E-F05D-4E2E-AB09-E031F501AF7F

The ID of the request.

RrpcCode String SUCCESS

The response code returned if the call is successful. Valid values:

  • UNKNOWN: A system error occurred.
  • SUCCESS: The request is successful.
  • TIMEOUT: The request times out.
  • OFFLINE: The device is offline.
  • HALFCONN: The specified device is offline within a heartbeat interval.
Success Boolean true

Indicates whether the call was successful.

  • true: The call was successful.
  • false: The call failed.


Sample requests
&<Common request parameters>

Sample success responses

XML format

<? xml version='1.0' encoding='UTF-8'? >

JSON format


Error codes

For a list of error codes, visit the API Error Center.