BACnet BBMD Virtual Device Pool for Network Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Broadcast management devices in building automation systems (BAS) face reliability issues due to failures, leading to unplanned downtime when they malfunction, as they are critical for communication between devices across subnets.
Innovation Solution
Implementing a pool of virtual devices with a backup broadcast management device that can sync data, detect failures, and switch roles to maintain communication reliability by transmitting health status messages, receiving responses, and selecting a suitable backup based on weighted health data, and periodically monitoring network and memory states.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single active broadcast management device is used to manage communication between subnets, then the system structure is simple and easy to operate, but the system reliability deteriorates due to unplanned downtime when the device fails
Solution Approach 1:
The patent implements a pool of virtual broadcast management devices that are pre-configured and stand by in advance. When the active device fails, one of the pre-configured virtual devices immediately takes over, eliminating unplanned downtime. This preliminary preparation of backup resources resolves the contradiction by ensuring reliability without requiring complex real-time failover mechanisms.
Solution Approach 2:
The patent creates virtual copies (virtual devices) of the broadcast management functionality that can assume the role of the active device. These virtual devices are software-based replicas that maintain the same communication management capabilities, allowing seamless failover and improving system reliability while keeping the physical infrastructure simple.
2Loss of time
If no backup device is implemented, then the device complexity remains low, but the loss of time increases due to unplanned downtime when the active device fails
Solution Approach 1:
The system pre-configures a pool of virtual broadcast management devices that are ready to take over immediately upon failure detection. This preliminary preparation eliminates the time loss associated with device failure and reconfiguration, as the virtual devices are already prepared and can assume the active role instantly, resolving the contradiction between minimizing downtime and maintaining simple system architecture.
3Reliability
If health status monitoring and automatic failover are implemented, then the reliability improves, but the device complexity increases due to additional monitoring and control mechanisms
Solution Approach 1:
The patent implements health status monitoring that continuously checks the active broadcast management device and automatically triggers failover when degradation is detected. This feedback mechanism ensures high communication reliability by detecting issues early and switching to a healthy virtual device, while the automated nature of the process minimizes the operational complexity burden on users.
Solution Approach 2:
The system performs self-diagnosis and automatic failover without requiring manual intervention. The health monitoring and failover mechanisms operate autonomously, detecting device degradation and switching to backup virtual devices automatically, which improves reliability while keeping the system easy to operate by eliminating the need for manual monitoring and intervention.
Data Source
AI summary
A building automation system includes a plurality of subnets, an active broadcast management device configured on at least one of the subnets, a pool of virtual devices communicably connected to the active broadcast management device, each of the virtual devices in the pool of virtual devices configured to store a broadcast distribution table (BDT), one or more processors, and memory coupled to the one or more processors and storing instructions. When executed by the one or more processors, the instructions cause the one or more processors to transmit a health status message to each available virtual device in the pool of virtual devices, receive a health status response from each of the available virtual devices, and select, according to the health status responses, at least one of the virtual devices from among the available virtual devices as a backup virtual broadcast management device to the active broadcast management device.