Copyright Goodheart-Willcox Co., Inc. 460 Security Essentials Baseband Baseband refers to a frequency’s original range before it is converted through mod- ulation. Modulation is the process of converting one frequency to another. For exam- ple, an audio signal transmitted on a radio frequency is modulated to a much higher, inaudible, frequency range used for radio broadcasts, cell phone conversations, and satellite transmissions. After the signal is transmitted, it is demodulated to the origi- nal baseband signal. Security implications include vulnerabilities within flawed firmware. Some smartphones and IoT devices operate with baseband vulnerabilities that enable attackers to execute a memory corruptions attack over the air. Additional consid- erations include vulnerabilities that enable attackers to monitor communication, place calls remotely, or transfer large volumes of data. Zigbee Zigbee is a telecommunication network standard based on IEEE’s 802.15.4 personal area network standard. It is considered an alternative to Wi-Fi and Bluetooth for some applications, including low-power sensors, such as the ones often found in home IoT sensors. For example, smart home devices, such as light bulbs that can be adjusted over wireless connections, are powered by Zigbee. Due to its prevalence in smart home and home automation appliances, security implications are important considerations to make when installing. Some Zigbee security standards are based on features included by the manufac- turer, so these standards likely vary from one device to another. The main security risks to Zigbee devices include theft of sensitive data, such as security encryption keys, from a node theft of the node itself unauthorized control of a node, such as from theft or replay attacks and loss of the service through jamming and other inter- ference attacks. 2.6 2.6 Narrowband signal Broadband signal Goodheart-Willcox Publisher Figure 14-8 Narrowband (NB) is a radio communication method that utilizes a narrow set, or band, of frequencies within a given communication channel.