Glossary

ad hoc (networks): Network Architecture; A temporary communication network formed directly by the participating devices, without the need for centralized infrastructure such as routers, telecommunications towers, or fixed access points. In this configuration, each device can act as both a terminal and an intermediary for data transmission, enabling communication between people even in environments where conventional infrastructure is unavailable.
Backhaul: Infrastructure; The connection that links a local telecommunications network to the internet's main infrastructure. When this connection is interrupted, several services and access points can lose communication at the same time, affecting neighborhoods, municipalities, or entire regions.
Benchmarking: Concept; Before choosing which technology to use in an emergency, it is important to analyze solutions that have already been tested in other contexts. Learning from previous experiences, identifying their results, limitations, and best practices, helps inform decisions and improve response strategies.
Broadcasting: Technology; The system for transmitting audio or audiovisual content to multiple receivers via radio waves. Used in AM and FM radio services and other transmission formats, it is an important means of disseminating information to the population, especially in emergency contexts and when other communication networks are disrupted.
Cascading Failure: Concept; The process by which the failure of one system or piece of infrastructure triggers successive failures in other interdependent systems. In disaster contexts, disruptions to essential services such as electricity, telecommunications, transportation, or water supply can compromise the functioning of other critical structures, amplifying the impacts of the initial event and hindering response and recovery efforts.
CB Radio (PX): Concept; A radiocommunication system that operates on the Citizen Band (CB), allowing voice communication over short and medium distances. Widely used by truck drivers, radio operators, and local communities, it can serve as an alternative means of communication in situations where other means are unavailable.
Cell Broadcast: Technology; A public alert system that sends emergency messages to all mobile phones present in a given area. Used in situations of imminent risk, such as floods, landslides, and severe storms, it allows guidance to be communicated quickly to the population without depending on apps or internet access. The messages are transmitted through the mobile network and reach devices located in the affected region simultaneously.
Cell Tower (ERB): Infrastructure; The telecommunications infrastructure responsible for connecting mobile devices to the cellular network through radio signals. Made up of antennas, transmission equipment, and power systems, it is a key element of mobile coverage. Damage or interruptions to its operation can compromise voice and data services in its coverage area.
Climate Disaster: Concept; Floods, droughts, windstorms, and heat waves are examples of extreme weather events that can become climate disasters when they affect vulnerable populations. Although they originate from meteorological phenomena or climate variability, their impacts also depend on social, economic, and environmental factors, such as poor infrastructure and lack of planning. That is why the same event can cause limited damage in a prepared region and severe consequences in another that is more exposed to risk.
COER: Standard; The Amateur Radio Station Operator Certificate, required to legally operate in the amateur radio service in Brazil. It is obtained free of charge through an online exam, organized into three classes (C, B, and A), which define the maximum allowed power and access to different frequency bands.
Communication Resilience: Concept; The ability to maintain or restore communication during situations of infrastructure failure, disruption, or degradation. This capacity can be strengthened through technology diversity, system redundancy, and the adoption of alternative means of communication in crisis or climate disaster scenarios.
Community Brigades: Concept; Organized groups of residents trained to act in the prevention and initial response to emergencies. In disaster situations, they often provide the first assistance to the population, helping with evacuations, fighting small fires, spreading information, and supporting affected people. Their work complements that of official emergency agencies, especially in hard-to-reach places or during the first hours after a critical event.
Critical Communication: Concept; The set of information and messages essential to protecting life, safety, and the continuity of services during emergency or disaster situations. It includes alerts, operational guidance, and communication between response teams, whose fast and reliable transmission is essential for reducing risks and supporting decision-making.
DC (direct current): Infrastructure; A type of electric current in which electrons flow in a single direction. It is used in batteries, solar panels, and various electronic devices. In emergency systems, it allows devices to be powered by alternative energy sources, helping to keep operations running even during interruptions to the conventional power supply.
Diátaxis: Concept; A documentation framework based on four complementary categories: tutorials, how-to guides, conceptual explanations, and reference material. The approach aims to make information easier to access according to the needs of the person reading the documentation, and is especially useful for sharing knowledge and producing manuals, procedures, and quick-reference content.
Direct-to-Cell: Technology; A satellite communication technology that enables a direct connection between satellites and compatible mobile phones, without the need for intermediary ground infrastructure within the coverage area. This approach expands connectivity in remote regions or areas affected by climate disasters, where conventional telecommunications networks may be unavailable or compromised.
Emergency Roaming: Cooperation Mechanism; A mechanism that allows the temporary use of mobile networks from different carriers during exceptional situations. Its purpose is to increase connectivity availability when part of the telecommunications infrastructure is compromised, helping to maintain communications in affected areas.
Environmental Racism: Concept; A concept that describes the unequal distribution of environmental risks and impacts among different social and racial groups. Historically marginalized communities often face greater exposure to environmental and climate threats, along with fewer conditions for prevention, response, and recovery in the face of climate disasters.
FANET: Network Architecture; (Flying Ad Hoc Network) is a network formed by unmanned aerial vehicles that communicate with each other to transmit data and extend communication coverage. This technology can be used in monitoring operations, emergency response, and temporary connectivity in areas where conventional infrastructure is unavailable or compromised.
Firmware: Software; The program written directly onto an electronic device, responsible for controlling its basic operation. Unlike regular applications, firmware sits close to the hardware and is usually updated less often. In network nodes, firmware defines how the device communicates, processes data, and interacts with other equipment in the mesh.
Gateway: Hardware; A device that connects different networks, allowing data to flow between them even when they use different technologies. In mesh networks, the gateway usually links the local radio network to other networks, such as the internet, acting as a bridge between what happens offline and the connected world.
GEO: Technology; (Geostationary Earth Orbit) refers to the geostationary orbit, located approximately 35,786 kilometers above the Earth's surface. Satellites positioned in this orbit remain apparently fixed relative to a point on Earth, allowing continuous coverage of large geographic areas. They are widely used in telecommunications, broadcasting, weather monitoring, and alert systems.
Hardware: Concept; The physical part of an electronic system, made up of tangible components such as boards, chips, antennas, batteries, and connectors.
HT Radio: Technology; (Handie-Talkie) is a portable radio used for voice communication between people. Because it operates directly by radio frequency, it can work independently of mobile phone networks or internet access. It is widely used by emergency teams, ham radio operators, firefighters, and volunteers in field operations and situations where other means of communication are unavailable.
IEEE 802.11: Standard; The family of technical standards that defines how wireless local area networks, known as Wi-Fi, operate. These standards establish how devices communicate by radio, ensuring interoperability between equipment from different manufacturers. Many technologies used in community, home, and corporate networks are based on IEEE 802.11.
IoT: Technology; (Internet of Things) is the set of physical devices connected to communication networks that are capable of collecting, transmitting, and, in some cases, processing data automatically. Sensors, meters, trackers, and monitoring equipment are examples of IoT devices. In the context of climate disaster prevention and response, these technologies can be used to track environmental conditions, monitor critical infrastructure, and generate alerts based on information collected in real time.
IP65 / IP68: Standard; Classifications that indicate a piece of equipment's degree of protection against the entry of dust and water. The higher the protection level, the greater the device's resistance to adverse environmental conditions. These classifications are important when choosing equipment intended for outdoor operations or exposure to rain, humidity, and dust.
ISM: Frequency Band; (Industrial, Scientific and Medical) refers to radio spectrum frequency bands originally intended for industrial, scientific, and medical applications, but which can also be used by various communication systems without an individual license. Technologies such as Wi-Fi, Bluetooth, and some emergency communication systems operate in these bands.
LEO: Technology; (Low Earth Orbit) refers to low Earth orbit, located a few hundred kilometers above the Earth's surface. Satellites positioned in this orbit offer lower communication latency compared to geostationary satellites and are widely used for internet access, monitoring, and Earth observation.
LibreMesh: Software; A set of open-source programs based on OpenWrt that makes it easier to build and manage mesh networks. Its configuration is distributed and automatic, allowing new equipment to join the network with little human intervention. LibreMesh is used mainly in community networks because it simplifies the deployment of collaborative, resilient infrastructure.
LilyGo: Technology; A line of low-cost electronic devices widely used in communication, monitoring, and experimental network projects. Many of its models support technologies such as LoRa, enabling the creation of messaging and data transmission systems in environments with limited infrastructure.
LoRa: Technology; A radio communication technology developed to transmit small amounts of data over long distances with low power consumption.
LoRaWAN: Protocol; (Long Range Wide Area Network) is a network protocol designed to manage devices that use LoRa technology. It defines how equipment connects, authenticates, and exchanges data over the network, enabling efficient communication for sensors and devices distributed across large areas.
Managed Flood Routing: Concept; A message-forwarding technique used in mesh networks, such as those built with Meshtastic, to prevent the same packet from being repeatedly retransmitted by multiple nodes at once. Each node that receives a new message waits a short, randomly chosen interval before rebroadcasting it; if, during that interval, it detects that another node has already retransmitted it, it cancels its own retransmission. This reduces radio congestion and battery consumption while keeping the message moving through the mesh until it reaches its destination.
MANET: Network Architecture; (Mobile Ad Hoc Network) is a network dynamically formed by mobile devices that communicate directly with each other without relying on fixed infrastructure. Each device can act as both a user and a data relay, helping maintain connectivity in environments where conventional networks are not available.
Mesh: Network Architecture; A communication architecture in which connected devices can relay data to one another. This structure creates multiple possible paths for transmitting information, increasing the network's resilience and reducing the impact of failures at individual points.
Meshtastic: Project; An open-source project that uses LoRa devices to create mesh networks for exchanging messages. The devices communicate directly with each other, without depending on the internet or mobile phone infrastructure, and are used in outdoor activities, remote regions, and emergency scenarios.
Mosaico System: Infrastructure; Anatel's system used to register Citizens Band (PX) stations and to issue and renew Amateur Radio (PY) licenses. PX station registration is free and has no expiration date; PY station licenses are valid for 20 years, renewable upon the operator's request.
NLOS: Concept; (Non-Line of Sight) is the ability of a communication system to transmit signals even when there is no direct line of sight between transmitter and receiver. This characteristic is important in urban environments, mountainous areas, or regions affected by disasters, where obstacles can hinder signal propagation.
Off-grid: Concept; Refers to systems that operate independently of the conventional power grid. They typically use their own energy sources, such as solar panels, batteries, or generators, ensuring that equipment and services keep working even during prolonged power outages.
Open Source: Concept; A development model in which a program's source code is made publicly available, allowing anyone to study, modify, distribute, and improve the software. This model favors transparency, collaboration, and the collective building of technology, and is the foundation of projects such as Meshtastic and LibreMesh, for example.
OpenWrt: Software; An open-source operating system for routers and other network equipment. It replaces the manufacturer's original software and offers greater flexibility for configuring, monitoring, and expanding the device's functionality. OpenWrt is widely used in community networks because it allows specific applications to be installed and the network's operation to be customized.
Optical Fiber: Infrastructure; A physical data transmission medium that uses pulses of light to carry information at high speed and with low signal loss. It is an essential part of telecommunications infrastructure, supporting internet, telephone, and digital service networks. Damage to the cables can significantly affect connectivity across entire areas.
PACE: Concept; A model used to organize communication plans in redundant layers, from the English acronym for Primary, Alternate, Contingency, Emergency. Each layer acts as a backup for the previous one: when the main means of communication fails, the operation moves to the next layer, down to the emergency resource.
PoE: Technology; (Power over Ethernet) is a technology that allows electrical power and data to be transmitted over the same Ethernet network cable. This approach reduces the need for additional electrical infrastructure and simplifies the installation of equipment such as cameras, access points, sensors, and communication devices in hard-to-reach locations.
PTT: Feature; (Push-to-Talk) is the button used on voice radios to start a transmission. While pressed, the radio transmits; once released, it returns to receive mode. It is recommended to press the PTT and wait about one second before speaking, to avoid the beginning of the message being cut off.
PY (Amateur Radio Prefix): Concept; One of the prefixes used to identify licensed amateur radio operators in Brazil. Amateur radio plays a relevant role in emergency communications, as its operators can set up alternative communication networks and support the exchange of information during disaster situations or infrastructure outages.
Repeater: Infrastructure; Equipment installed at elevated points that receives a radio signal and rebroadcasts it, significantly extending the range of voice radio communication. In emergency situations, repeaters linked to HT radios or amateur radio stations can be the only fully functional means of communication in an isolated region.
Restricted Radiation: Standard; A category of radiocommunication services exempt from individual licensing, as they operate with limited power and according to technical parameters set by Anatel. Citizens Band radio (PX) is an example of a restricted radiation service, requiring only free registration, with no station license needed.
RoIP: Technology; (Radio over IP) is a technology that integrates radiocommunication systems with IP-based networks. It enables the exchange of messages and calls between radios, computers, and other devices connected to the network, extending the reach and interoperability between different communication systems.
SANET: Network Architecture; (Smart Aquatic Network or Sensor-Aided Aquatic Network) is a network architecture designed for communication and monitoring in aquatic environments. It can be used for environmental data collection, hydrological monitoring, and support for operations in rivers, lakes, reservoirs, and flood-prone areas.
Sensors (IoT): Technology; (IoT - Internet of Things) are devices capable of automatically monitoring variables such as water level, humidity, temperature, land movement on slopes, and other environmental conditions. The collected data is transmitted to monitoring and alert systems, allowing for the early identification of risks and changes that may indicate the occurrence of disasters.
Silence Zones: Concept; Areas with nonexistent or insufficient coverage of communication services, such as mobile telephony, internet, or radiocommunication. These limitations can result from geographic features, a lack of infrastructure, or damage caused by disasters, making it harder to access information and coordinate response actions.
Topology: Network Architecture; The way a network's devices are organized and connected to one another, both physically and in terms of communication. Topology influences a network's performance, reliability, and ability to expand. In community and disaster-response networks, mesh topologies are common, in which equipment can connect through different paths, increasing resilience if a given point stops working.
TVWS: Technology; (TV White Spaces) refers to the use of unoccupied television frequencies in a given region for data transmission. Due to its wide range and greater ability to overcome obstacles compared to other frequency bands, this technology can be used to extend connectivity in remote areas and support emergency communications.
VANET: Network Architecture; (Vehicular Ad Hoc Network) is a network architecture formed by vehicles capable of exchanging information directly with each other and with other communication systems. This structure allows data about location, road conditions, and emergency operations to be shared, contributing to the coordination of teams and resources in the field.
Vox: Feature; (Voice Operated Transmission) is a feature found in some radios and communication systems that automatically activates transmission when it detects a person's voice. This feature allows communication without the need to press buttons, making it easier to use during operational activities and emergency situations.
VSAT: Infrastructure; (Very Small Aperture Terminal) is a satellite communication ground station made up of a small antenna and associated equipment. Used to provide connectivity in remote locations or areas affected by climate disasters, it allows access to voice and data services independently of conventional terrestrial networks.
Wi-Fi: Technology; A wireless communication technology that allows devices to connect to local networks and the internet via radio frequency. Widely used in homes, businesses, and public spaces, it can also be used to provide temporary connectivity in shelters, command centers, and areas affected by emergencies.
Wi-Fi HaLow: Technology; (IEEE 802.11ah) is a variant of Wi-Fi developed to offer greater range and lower power consumption. Operating at lower frequencies than conventional versions, it is especially suited for monitoring applications, the Internet of Things, and coverage of large areas.
WMN: Network Architecture; (Wireless Mesh Network) is a wireless network architecture based on multiple interconnected nodes that can relay data to one another. This structure extends network coverage and increases its resilience, allowing communications to be maintained even when some points stop working.