Copy of Thing categories

By looking into today’s state of the hardware, electronics and software combination, things can be put into three categories

Sensors and Actuators (Field Devices) - These devices are mostly analog and when digital, function remains singleton. Electronics is simple circuit to  actuate the function. Controllers are used to create a system of multiple field devices. i.e Temperature Sensor, Linear Actuator, etc.

To connect Sensors and Actuators to Application tier, Micro Controller Units (MCU) are used. MCU's connect on serial protocols (mostly) with computers (mostly gateways) where TQLEngine runs.

Devices - These hardware have electronics and software inside the device. Device has fixed set of functions, which are exposed through messaging structures over serial or IP based communication protocols. Device maintains its logic internally by having a dedicated controller. i.e. Automatic sprinkler controller, Nest Thermostat, etc.

Devices can be connected directly to TQLEngine (running on the gateway or through gateway running on the server).

Machines - are high end devices, which provide set of applications to interact with the devices in the machine. These applications are rich way to interact with machine. i.e. CTScanner, gas turbine, etc.

Machines are conversed with TQLEngine through IP based protocols in general.

There are following message styles used in the things world

Request-Response

Devices respond to request only and blocking in nature. Every request has a response pattern and either request or response can be constituted in one or more message blocks. Most of the simple business devices like Patient Monitor, Infusion Pump, printer, etc. fall under this category.

Asynchronous Send Only

These devices are capable of sending data, once they recognize the listener attached. The format of the data is predefined. Most of the sensors like temperature, humidity, etc. are send only devices.

Asynchronous Receive-Send Both

These devices are responsive and can receive messages or send messages. Mostly receiving messages are used for actuation or configuration. Sending messages are for alerts or states. Most of the industrial devices like valves, pumps, etc fall under this category.

Transactional

Transactional devices are most modern category of devices, who can except a dialog between themselves and the client. Each command can take a form of dialog and acceptance or rejection of the dialog can be in entirety maintain the integrity of the device. Examples are TL-1 based network devices.