@@ -81,25 +81,25 @@ As defined previously, an IoT Agent is a component that lets a group of devices
8181Context Broker using their own native protocols. Every IoT Agent is defined for a single payload format, although they
8282may be able to use multiple disparate transports for that payload.
8383
84- We have already encountered the Ultralight IoT Agent, which communicates using a simple bar (` | ` ) separated list of
84+ We have already encountered the JSON IoT Agent, which communicates using a simple bar (` | ` ) separated list of
8585key-value pairs. This payload is a simple, terse but relatively obscure communication mechanism - by far the commonest
8686messaging payload used on the Internet is the so-called JavaScript Object Notation or JSON which will be familar to any
8787software developer.
8888
89- JSON is slightly more verbose than Ultralight , but the cost of sending larger messages is offset by the familiarity of
89+ JSON is slightly more verbose than JSON , but the cost of sending larger messages is offset by the familiarity of
9090the syntax. A separate
9191[ IoT Agent for JSON] ( https://fiware-iotagent-json.readthedocs.io/en/latest/usermanual/index.html#user-programmers-manual )
9292has been created specifically to cope with messages sent in this format, since a large number of common devices are able
9393to be programmed to send messages in JSON and many software libraries exist to parse the data.
9494
95- There is no practical difference between communicating using a JSON payload and communicating using the Ultralight plain
95+ There is no practical difference between communicating using a JSON payload and communicating using the JSON plain
9696text payload - provided that the basis of that communication - in other words the fundamental protocol defining how the
9797messages are passed between the components remains the same. Obviously the parsing of JSON payloads within the IoT
9898Agent - the conversion of messages from JSON to NGSI and vice-versa will be unique to the JSON IoT Agent.
9999
100100A direct comparison of the two IoT Agents can be seen below:
101101
102- | IoT Agent for Ultralight | IoT Agent for JSON | Protocol's Area of Concern |
102+ | IoT Agent for JSON | IoT Agent for JSON | Protocol's Area of Concern |
103103| ------------------------------------------------------------------- | ------------------------------------------------------------------- | -------------------------- |
104104| Sample Measure ` c\|1 ` | Sample Measure ` {"count": "1"} ` | Message Payload |
105105| Sample Command ` Robot1@turn\|left ` | Sample Command ` {"Robot1": {"turn": "left"}} ` | Message Payload |
@@ -531,7 +531,7 @@ GET or POST requests to:
531531http://iot-agent:7896/iot/json?i=<device_id>&k=4jggokgpepnvsb2uv4s40d59ov
532532` ` `
533533
534- Which is very similar syntax to the Ultralight IoT Agent - only the path has changed. This allows multiple IoT Agents to
534+ Which is very similar syntax to the JSON IoT Agent - only the path has changed. This allows multiple IoT Agents to
535535listen at different locations.
536536
537537When a measurement from an IoT device is received on the resource URL it needs to be interpreted and passed to the
@@ -625,7 +625,7 @@ curl -iX POST \
625625 -d '{"c": "1"}'
626626` ` `
627627
628- Both the payload and the `Content-Type` have been updated. The dummy devices made a similar Ultralight request in the
628+ Both the payload and the `Content-Type` have been updated. The dummy devices made a similar JSON request in the
629629previous tutorials when the door was unlocked, you will have seen the state of each motion sensor changing and a
630630Northbound request will be logged in the device monitor.
631631
@@ -789,7 +789,7 @@ command can be seen in the value of the `ring_info` attribute.
789789
790790# ## Provisioning a Smart Door
791791
792- Because the underlying Ultralight and JSON protocols are so similar, actuators and devices are provisioned using the
792+ Because the underlying JSON and JSON protocols are so similar, actuators and devices are provisioned using the
793793same attributes as the data the IoT Agent needs to know to communicate with the device reamins the same, and the payload
794794parsing NGSI to JSON is delegated to the IoT Agent itself. Provisioning a device which offers both commands and
795795measurements is merely a matter of making an HTTP POST request with both `attributes` and `command` attributes in the
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