Encryption is an evasion technique that is a function of ransomware, which is a type of malware that encrypts the victim's files or system and demands a ransom for the decryption key. Encryption is used by ransomware to prevent the victim from accessing their data and to avoid detection by antivirus or other security tools.
Encryption can also be used by other types of malware to hide their communication, configuration, or payload from analysis. References:
* Understanding Cisco Cybersecurity Operations Fundamentals (CBROPS) v1.0, Module 3: Network Intrusion Analysis, Lesson 3.4: Malware
* Cisco Certified CyberOps Associate Overview, Exam Topics, 3.4 Compare and contrast types of malware

Digital certificates are essential for decrypting ingress and egress perimeter traffic, as they provide the necessary encryption keys for secure communications. By using digital certificates, network security devices can inspect the decrypted traffic to detect any malicious outbound communications that may indicate command-and-control activity.

To analyze both payload and header information, an engineer must capture the full packet data. This includes all protocol and payload information for the traffic, allowing for a comprehensive analysis of the data being transmitted5678. References: Full packet capture is a common practice in network monitoring and security, as it provides detailed insights into the data transmitted over the network, including both payload and header information