# IoT Networking ## What is the Internet of Things The Internet of Things, or IoT, refers to the network of physical objects embedded with sensors, software, and other technologies that connect and exchange data with other devices and systems over the internet. IoT devices range from simple sensors measuring temperature or humidity to complex industrial machinery, smart home devices, medical monitoring equipment, and autonomous vehicles. The number of IoT devices worldwide is in the tens of billions and continues to grow rapidly. ## IoT Communication Challenges IoT devices face unique networking challenges compared to conventional computers. Many IoT devices are battery-powered and must operate for months or years on a single battery, requiring extremely low power consumption. IoT devices are often deployed in large numbers in dense environments, requiring network protocols that can support many devices simultaneously. IoT devices may be in locations with poor connectivity, requiring protocols that work over long ranges or through obstacles. IoT devices are often low-cost and have limited processing power and memory, restricting what protocols they can run. ## Short-Range IoT Protocols Bluetooth Low Energy is widely used for short-range IoT communication. It is designed for devices that transmit small amounts of data infrequently, such as fitness trackers and beacons. Zigbee and Z-Wave are designed for home automation and building control. They form mesh networks where devices can relay messages from other devices, extending coverage. Thread is a newer IPv6-based mesh networking protocol for home IoT devices. WiFi is used for IoT devices that require higher bandwidth or are already connected to a WiFi infrastructure. ## Long-Range IoT Protocols LoRaWAN, Long Range Wide Area Network, uses LoRa radio technology to transmit small amounts of data over distances of several kilometers with very low power consumption. It is used for applications like smart meters, agricultural monitoring, and asset tracking. Sigfox is another low-power wide-area network technology for IoT. Narrowband IoT, or NB-IoT, and LTE-M are cellular-based IoT protocols standardized by 3GPP that run on existing cellular network infrastructure. ## IoT Security IoT security is a major concern because many IoT devices have limited security capabilities and are deployed in large numbers. Common IoT security problems include default credentials that are never changed, lack of encryption, inability to receive security updates, and devices that collect sensitive data without adequate protection. Compromised IoT devices have been used in large-scale distributed denial of service attacks. Best practices include using unique credentials for each device, encrypting all communications, keeping firmware updated, and isolating IoT devices on a separate network segment.