## 3 Security and Privacy Attacks and Threats in EC-Based IoT
The most widely adopted authentication protocols in edge computing are Wi-Fi-protected access (WPA/WPA2) and secure sockets layer (SSL)/transport layer security (TLS) protocols; (3) attacks exploiting vulnerabilities in authorization protocols, in which attackers usually exploit the design weaknesses or logic flaws existing in authorization protocols to gain unauthorized access to the sensitive resources or perform privileged operations. The most widely adopted authorization protocol in edge computing is the open authorization (OAuth) protocol [103, 104]; (4) Overprivileged attacks, which can happen if an app or a device is granted stronger access rights or more than what is needed. _4. Jamming attack_ is a special type of denial-of-service (DoS) attack. The network will be flooded intentionally by attackers using counterfeit messages to exhaust communication, computing, or/and storage resources. This attack will make authorized users unable to use the infrastructure of the EC-based IoT network [33, 92, 105]. _5. The most famous types of distributed denial-of-service (DDoS) attacks_[101, 106] against EC nodes are outage attacks, sleep deprivation, and battery draining. In outage attacks, EC nodes do not perform their normal operations because of unauthorized access by attackers. In sleep deprivation, attackers overwhelm EC nodes with too many legitimate requests. This kind of attack is very hard to detect. In battery draining, the batteries of sensors, devices, or EC nodes are depleted; therefore, node failure or outage occurs. The most common DDoS attack at the communication level is jamming the transmission of signals, including continuous jamming over all transmissions and intermittent jamming by sending/receiving packets periodically by EC nodes [32, 98, 99, 100, 105, 107, 108, 109, 110, 111]. DDoS attacks in edge computing can be classified as flooding-based attacks and zero-day attacks. In flooding-based attacks (e.g., UDP flooding, SYN flooding, HTTP flooding), the attacker tries to saturate the server and shut down the normal service of a server by flooding with malicious/malformed network packets. A zero-day attack is more difficult to implement. In zero-day DDoS attacks, the attacker should find an unknown vulnerability, i.e., a zero-day vulnerability in the code running on the target edge device/server. These vulnerabilities can trigger memory failure/corruption, resulting in a service shutdown. A zero-day attack is also difficult to defend since it exploits a zero-day unknown vulnerability. _6. Physical attacks/tampering_ happen when attackers can access the EC nodes/devices physically. Then, attackers can extract valuable and sensitive cryptographic data, tamper with the circuit, or modify software/operating systems [33, 92]. 7. _Eavesdropping or sniffing attacks_ occur when adversaries covertly listen to private conversations, such as usernames, passwords, etc., over communication links. Attackers will be able to gain crucial information about the network, for instance, when sniffed packets contain control or access information of the EC nodes, such as configurations and identifiers of nodes or passwords of the shared network [92, 98, 105]. 8. EC nodes can reveal critical information even when they are not transmitting any data as nonnetwork side-channel attacks. For example, the detection of known electromagnetic/acoustic signals or protocols from medical devices can lead to serious privacy issues since critical information about the patient and device can be leaked [8, 92]. 9. By redirecting, misdirecting, spoofing, or dropping data packets at the communication level, attackers can change routing information and affect how messages are routed [8, 92, 105].