Which security mechanism is used to ensure the integrity and authenticity of data in IoT communications? Group of answer choicesDigital signaturesTwo-factor authenticationPublic key infrastructure (PKI)Data encryption

The security mechanism used to ensure the integrity and authenticity of data in IoT communications is Digital signatures.

Here's a step-by-step explanation:

1. Digital signatures are a cryptographic tool that helps in validating the authenticity and integrity of a message, software or digital document.

2. In the context of IoT, digital signatures are used to ensure that the data being communicated between devices has not been tampered with and is from a verified source.

3. This is done by creating a unique signature for each piece of data using a private key known only to the sender.

4. The receiver can then use the sender's public key to verify the signature and confirm that the data has not been altered in transit and that it came from the sender.

5. Therefore, digital signatures provide a layer of credibility and security to the data, making it an essential security mechanism in IoT communications.

Note: While Two-factor authentication, Public key infrastructure (PKI), and Data encryption are also security mechanisms, they serve different purposes. Two-factor authentication is used for verifying the identity of users, PKI is a set of roles, policies, and procedures needed to create, manage, distribute, use, store & revoke digital certificates and manage public-key encryption, and Data encryption is used for protecting sensitive information by transforming it into an unreadable format.