Simple Network Management Protocol (SNMP) is designed for managing and monitoring network devices. Administrators use SNMP to query devices for configuration information, performance metrics, and operational status. This capability is fundamental to ensuring security and compliance, as it allows for the continuous monitoring of device configurations against established security baselines, tracking unauthorized changes, and collecting data for security audits. SNMPv3, the current standard, includes robust security features such as authentication and encryption, which securely facilitate these management and monitoring tasks, making it a direct tool for enforcing security policy and verifying compliance.

A. NTP (Network Time Protocol): NTP synchronizes time across network devices. While accurate timestamps are critical for correlating log files during security incident investigations, NTP itself does not monitor or manage network security policies.

C. DHCP (Dynamic Host Configuration Protocol): DHCP automates the assignment of IP addresses. Its primary function is not security or compliance, although features like DHCP snooping provide protection against specific attacks like rogue DHCP servers.

D. DNS (Domain Name System): DNS resolves domain names to IP addresses. While analyzing DNS traffic can be part of a security strategy, the protocol's core purpose is name resolution, not network-wide security management or compliance.

1. Cisco Systems, Inc., "SNMP Configuration Guide, Cisco IOS XE Gibraltar 16.12.x". This guide states, "SNMP provides a standardized framework and a common language used for the monitoring and management of devices in a network." The document details how SNMP is used to access and modify management information, which is the basis for compliance checking and security monitoring. (Reference: Chapter: "SNMP Configuration Guide," Section: "Information About SNMP")

2. Kurose, J. F., & Ross, K. W., Computer Networking: A Top-Down Approach. In the chapter on Network Management, the text explains that SNMP is the primary protocol for "managing (e.g., setting and querying configuration information and statistics) a network." This management capability is essential for ensuring devices comply with organizational security policies. (Reference: Chapter 9: "Network Management," Section 9.1: "What is Network Management?")

3. National Institute of Standards and Technology (NIST), "Special Publication 800-41 Rev. 1: Guidelines on Firewalls and Firewall Policy". This document frequently references the use of management protocols like SNMP for monitoring firewall status and logs, stating, "Administrators should also monitor the status of firewalls... This can be done through a variety of methods, such as... Simple Network Management Protocol (SNMP) traps." (Reference: Section 5.3, "Firewall Logging")