Proofpoint – The Importance of Enterprise Scale for User Activity Monitoring

logz.io – Using Audit Logs for Security and Compliance

Environmental Protection Agency – Audit and Accountability Procedure

log.io – The Complete Guide to the ELK Stack

SolarWinds – Audit policies and best practices for SEM

Internet Engineering Task Force – Network Time Protocol Best Current Practices

Carnegie Mellon University – Best Practices for NTP Services

NIST Authenticated NTP Service

Cisco – Network Time Protocol: Best Practices White Paper

Open Web Application Security Project (OWASP) – Logging Cheat Sheet OWASP