The syslog protocol is a standard for message logging, defined by the Internet Engineering Task Force (IETF) in RFC 5424. Its primary function is to provide a standardized transport mechanism to collect log and event messages from a wide variety of network devices and systems (e.g., firewalls, routers, servers) and forward them to a central repository, known as a syslog server. In security operations, this centralized collection is fundamental for monitoring, auditing, and incident analysis, as it allows security information and event management (SIEM) systems to correlate events from across the entire IT infrastructure. Syslog itself does not analyze data or block threats; it is the foundational protocol for log aggregation.

A. Syslog is a protocol for transporting log data; it does not perform the analysis or detection characteristic of an Intrusion Detection System (IDS).

B. Actively blocking network traffic is the function of a firewall or an Intrusion Prevention System (IPS), not a logging protocol like syslog.

D. File scanning and malware detection are functions of endpoint security solutions like antivirus or Endpoint Detection and Response (EDR) tools, not syslog.

1. Gerhards, R. (2009). The Syslog Protocol. IETF. RFC 5424. Section 1, "Introduction". Retrieved from https://doi.org/10.17487/RFC5424. The document states, "This document describes the syslog protocol, which is used to convey event notification messages."

2. Cisco. (n.d.). System Message Logging. Cisco IOS Configuration Fundamentals Command Reference. In the "Logging System Messages" section, it is described as a method to "send messages to a central syslog server," which facilitates "logging of events."

3. Purdue University. (n.d.). Introduction to Logging and Monitoring. Courseware for CS 42600, Computer Security. The course materials describe syslog as the de facto standard protocol for forwarding log messages from devices to a central server for collection and review.