AMQP Client Access

Protocol Version

The platform supports only AMQP 1.0.

Connection Establishment and Authentication

1. The AMQP client establishes a TCP connection with the platform and performs TLS handshake verification.
   

   For security, the AMQP client must use TLS 1.2 for encryption. Non-encrypted TCP transmission is not supported. The difference between the client time and standard time cannot be greater than 5 minutes. Otherwise, the connection will fail.

2. The client requests to set up a connection.
3. The client sends a request to the platform to establish a receiver link (a unidirectional channel for the platform to push data to the client). The receiver link must be set up within 15 seconds after the connection is set up on the client. Otherwise, the platform will close the connection. After the receiver link is set up, the client is connected to the platform.
   

   A maximum of 10 receiver links can be created for a connection, and sender links cannot be created. Therefore, the platform can push messages to the client, but the client cannot send messages to the platform.

Connection Configuration

The table below describes the connection address and connection authentication parameters for the AMQP client to connect to the platform.

• AMQP access address: amqps://${server.address}:5671

• Connection string: amqps://${server.address}:5671?amqp.vhost=default&amqp.idleTimeout=8000&amqp.saslMechanisms=PLAIN

  Parameter	Description
  server.address	AMQP server access address. Obtaining method: Log in to the console, choose IoTDA Instances, and click the target instance card. In the navigation pane, choose Overview. Check the access information in the Instance Information area, and obtain the AMQPS access address. Figure 1 Obtaining access information
  amqp.vhost	Currently, AMQP uses the default host. Only the default host is supported.
  amqp.saslMechanisms	Connection authentication mode. Currently, PLAIN-SASL is supported.
  amqp.idleTimeout	Heartbeat interval, in milliseconds. If the heartbeat interval expires and no frame is transmitted on the connection, the platform closes the connection.

• Port: 5671
• Client identity authentication parameters

  username ="accessKey=${accessKey}|timestamp=${timestamp}|instanceId=${instanceId}"

  password = "${accessCode}"

  Parameter	Mandatory	Description
  accessKey	Yes	Description: An access key can be used to establish a maximum of 32 concurrent connections. When establishing a connection for the first time, preset the parameter by following the instructions provided in AMQP Access Credential.
  timestamp	No	Description: The 13-digit millisecond-level timestamp of the current time, which is transferred by the client. When this parameter is provided, the server compares the timestamp to its current time and rejects the request if the difference exceeds 5 minutes.
  instanceId	No	Description: Instance ID. This parameter is mandatory when multiple instances of the standard edition are purchased in the same region. For details, see Viewing Instance Details.
  accessCode	Yes	Description: The value can contain a maximum of 256 characters. When establishing a connection for the first time, preset the parameter by following the instructions provided in AMQP Access Credential. If the accessCode is lost, you can call the API for generating an access credential (see Generating an Access Credential) or follow the instructions provided in AMQP Access Credential to reset the accessCode.

AMQP Access Credential

If an application uses AMQP to access the platform for data transfer, preset an access credential. You can call the API for generating an access credential (see Generating an Access Credential) or use the console to preset an access credential. The procedure for using the console to generate an access credential is as follows:

1. Choose IoTDA Instances, select the edition of your instance, and click Details to go to the instance details page.
2. Click Preset Access Credential to preset the accessCode and accessKey.
   Figure 2 Instance management - Preset access credential
   
   

   If you have preset an access credential before, the previous access credential cannot be used after the presetting.

Connection Specifications

Message Receiving

After the receiver link between the client and platform is established, the client can proactively pull data or register a listener to enable the platform to push data. Proactive pulling is recommended, as it allows the client to retrieve data according to its own capacity.