Silvanet FAQ

Contents

• Networking FAQs

• Silvanet Deployment FAQs

• Silvanet Suite FAQs

• Silvanet Sensor FAQs

• Silvanet Mesh Gateway FAQs

• Silvanet Border Gateway FAQs

• Fire detection FAQs

Networking FAQs

What is a Data Packet?

Not to be confused with Silvanet Packets, data packets are defined by the ISO model. They are data units within the Network Layer. They include the source and destination IP addresses as well as other information. Data packets are, essentially, a connection-oriented protocol. They ensure each single packet is not dropped or compromised and are considered a reliable form of communication. An acknowledgement (ACK) packet is usually sent as a reply to a received data packet. If no ACK packet is received, the data packet is simply resent. LoRa uses data packets to communicate between LoRa enabled devices (sensors and gateways) and are part of the definition of a LoRaWAN network.

What is FUOTA?

Firmware update Over the Air (FUOTA) is a standard for distributing firmware updates using unicast or multicast. It allows firmware updates to be delivered to many devices (Silvanet Sensors) at the same time efficiently and securely.

The Silvanet Cloud (Network Server) enables class C in LoRaWAN and prepares to send updates as a multicast distribution. The firmware is chunked into transmittable parts. The Silvanet Cloud schedules each update chunk as a download message to the multicast group. The Network Server then verifies that each device has received all chunks, synthesizes them and verifies the update signature.

The end device (Silvanet Sensor) applies the firmware update and delivers a firmware update complete uplink message to the Network Server.

What is LoRa?

LoRA is a wireless modulation technique based on Chirp Spread Spectrum (CSS) where a CHIRP (Compressed High Intensity Radar Pulse) is a signal that carries data. Chirps have two types of signals - an up-chirp and a down-chirp. An up-chirp increases in frequency while a down-chirp decreases in frequency. LoRa is ideal for IOT applications like the Silvanet sensor as they transmit small data packets with low bit rates. LoRA has an advantage over other techniques such as ZigBee as data can be transmitted at longer ranges. This allows Gateways to be located at greater distances from sensors, thus reducing the number of gateways required per deployment.

What is LoRaWAN?

LoRaWAN is built on top of LoRa in the MAC layer. It defines how devices use the LoRa hardware, such as when the devices can transmit and receive messages, as well as the format of the messages. LoRaWAN is optimized to operate in low power mode and can transmit as far as 10 km in open fields, less in forests and up to 3 km in urban areas with significant interference. LoRaWAN also allows for firmware updates and updates to the ML Model on sensors over the air (FUOTA).

What is MQTT?

MQTT is a Client Server publish/subscribe messaging transport protocol that is lightweight, open, simple, and designed to be easy to implement. Typically used for communication in Machine to Machine (M2M) and Internet of Things (IoT) contexts where a small code footprint is required and/or network bandwidth is at a premium. It is used by third-parties to communicate with a Silvanet Network.

Silvanet Deployment FAQs

What is a Deployment Packet?

A Packet defines the Silvanet sensors and gateways that are to be deployed in a Site. Silvanet Deployment Packets are created in the Site Management app and assigned to users for deploying devices in a Site. Each Packet includes a list of Silvanet devices to be deployed and the location (GPS coordinates) where each device is to be deployed. When a device is deployed to a location, a user scans in the device’s QR Code which then syncs the device’s actual location to the corresponding entry in the Silvanet Cloud.

What is a Silvanet Site?

A Site is a geographical area (defined in Km² or square miles) where a network of sensors and gateways are deployed to monitor the forest environment. Sites are set up by Dryad administrators (currently, Dryad only) and assigned to registered users. Within a Site, the number and location of sensors and gateways are defined. The Site Management app (dryad.app) displays all Sites that Dryad has created and administered for you. Using your username and password, you are granted access to all Sites to which you are registered. After deployment, a Site can be monitored within the Site Management app.

Silvanet Suite FAQs

Why are supercapacitors used in Silvanet Devices?

A supercapacitor is a high capacity capacitor that can accept and deliver charges faster than batteries and tolerates many more charge and discharge cycles than rechargeable batteries. It provides a large amount of power for a relatively short time. It is best suited for applications where a very high number of charge/discharge cycles or longer lifetime is required. They also have low risk of spark hazard. This makes them ideal for energy storage for Silvanet devices which are installed in forests. They are used because the sensors and gateways should not themselves be a source of fire ignition.

Which Gateways are used in the Silvanet System?

Silvanet deploys two types of gateways: a Mesh Gateway and a Border Gateway.

Mesh Gateways receive messages from sensors and forward them using the LoRaWAN mesh network to other Mesh Gateways within range and finally to one or more Border Gateways. Messages sent from sensors hop through all Mesh Gateways within range.

Border Gateways receive messages from Mesh Gateways and Silvanet Wildfire sensors (if they are in range) using the LoRaWAN mesh network and forwards them using one of three services - 4G, Ethernet or SWARM satellite to the Silvanet Cloud.

Silvanet Sensor FAQs

How long does a sensor need to calibrate to a new deployment location?

Once deployed, the Silvanet sensor needs to perform a calibration to determine a value for normal air in the environment around the sensor. This is critical for allowing the sensor to detect a smoldering fire. The calibration period is approximately 14 days after deployment and during this period the sensor does not detect smoldering fires.

What happens if a deployed sensor is handled while on a tree?

If a Silvanet sensor is touched or moved while deployed on a tree, it causes interference with the calibration. The gas sensor in the Silvanet sensor is very sensitive to outdoor changes. Consequently, moving, touching or interacting with the sensors beyond what is necessary influences the sensor readings and also the sensor calibration settings.

For the sensor to return to normal values, the sensor needs at least 1 hour to stabilize and return to its base readings. Consequently, the sensor does not measure any changes in the environment if a test is run during this stabilization period.

We strongly advise leaving the sensors alone once they are deployed.

What is meant by interacting with a deployed sensor?

Interacting with sensors includes:

• Touching the sensors in any way
• Moving the sensors in any way
• Being in proximity to the sensors
• Having running vehicles nearby the sensor
• Bringing any source near the sensor that could trigger the Phase 1 alert such as cigarettes, running machinery (especially with diesel motors) and even breathing on the sensor.

How high should a sensor be attached to a tree?

If possible, install the Silvanet sensor at least 3 meters above the forest floor, depending on available sunlight in the location. At this height, the device has less interference from human or animal interactions.

Silvanet Mesh Gateway FAQs

How high should a Mesh Gateway be attached to a tree?

If possible, install the Silvanet Mesh Gateway at least 3 meters above the forest floor, depending on available sunlight in the location. At this height, the device has less interference from human or animal interactions.

Silvanet Border Gateway FAQs

How is the Border Gateway connected to the Solar Panel

The solar panel is pre-connected to the Border Gateway. If it needs to be disconnected for any reason, the wiring is as follows:

• Negative: Brown wire

• Positive: White wire

How long does it take for the solar panel to charge the Border Gateway supercapacitors?

When the Border Gateway is connected to the solar panel, the Border Gateway requires 3 to 4 hours before it comes online after the solar panel begins charging the supercapacitors in the Border Gateway. If the Border Gateway is moved from using PoE to using the solar panel, the Border Gateway needs 1 to 2 days to begin operating properly.

How do I determine if the solar panel is damaged

First, disconnect the solar panel from Border Gateway (one wire is enough) and measure the voltage. It should be around 20V. If not, then there is not enough light or the solar cell is damaged.

Then Use an 18-24V power supply instead of the solar cell and wait.

What type of PoE can be used with the Border Gateway?

The Border Gateway requires a PoE Injector (Adapter) that provides a voltage range of between 36V and 57V. The PoE must be IEEE 802.3af compliant.

Fire detection FAQs

How is a ML model used in Silvanet?

A Machine Learning (ML) model is a program that has been trained to recognize certain types of patterns. You can train a model over a set of data, providing it an algorithm that it can use to make predictions and learn from those data. ML models find patterns and make decisions in previously unseen data and make predictions about that data. A ML Model recognizes patterns by having it “trained” with large datasets. Training involves optimizing the machine learning algorithm to find certain patterns or outputs from the dataset. The output - a ML Model - is a computer program with specific rules and data structures.

What are Volatile Organic Compounds (VOC)?

A VOC (Volatile Organic Compound) is an organic chemical compound that evaporates easily at room temperature. They vaporize into air and dissolve in water. Organic compounds are chemicals that contain carbon and are found in all living things, especially trees. VOCs are also emitted from oil and gas fields and diesel exhaust. From the US EPA: “Any compound of carbon, excluding carbon monoxide, carbon dioxide,” and related chemicals.

How is fire intensity measured?

The most important measure of fire behavior is fire intensity. Fire intensity (I) represents the heat released per meter of fire front (kW/m of fire front). It is a function of (1) heat yield of fuel (kilojoules/kg), (2) amount of fuel per unit area (kg/m2) and (3) the rate of forward spread of fire front (km/h).