Devices

Overview

We use the term device to describe any asset that is microprocessor based. Typically, this includes most IT and networking gear, but also includes microprocessor based controllers commonly used to perform control and monitoring of equipment.

There can often be a fuzzy distinction between equipment versus devices, especially since most point data for an equipment is manifested through a controller. However when building a detailed model of a control system, use an equip entity to represent the physical asset and use a separate device entity to represent the controller. In cases where the distinction is not clear, then combine the equip and device tags into one entity.

Networks

Networks are modeled with the network tag. Devices on a network should model their network relationship with the networkRef tag.

Devices where the main function is networking should subtype from the networking-device conjuct. Haystack defines the following networking device types:

• networking-router: device used to route data between different networks
• networking-switch: device used to connect devices on the same network

Here is a simple example of a network model that includes a switch with two controllers:

id: @my-network
dis: "Simple Local Network"
network

id: @my-switch
dis: "Network Switch"
networking
switch
device
networkRef: @my-network

id: @my-controller-1
dis: "Controller 1"
controller
device
networkRef: @my-network

id: @my-controller-2
dis: "Controller 2"
controller
device
networkRef: @my-network