Reading data using token

To support READ commands, devices must listen or SUBSCRIBE to the following topic:

${token}/server/commands/${serialNumber}

The value received in the PUBLISH message will be the resource path to be read.

The resource path is used by the Device to identify the data element to be read and should confirm to

the /object/objectInstance/resource/resourceInstanceId URI format as used when collecting data.

For example:

The device SUBSCRIBE to topic t8cwp2uneipj/server/commands/8800002400000 to IMPACT.

IMPACT receives a request to read data from the device.

IMPACT sends a PUBLISH with topic t8cwp2uneipj/server/commands/8800002400000 with value parking/0/timer.

The Device sends a PUBLISH t8cwp2uneipj/8800002400000/parking/0/timer with value 27 to IMPACT.

Within the device, care must be made to ensure that the device responds within a reasonable time, say 10 seconds. If this is not the case the IMPACT server will time out.