802.1X is the gatekeeper of modern enterprise networks, ensuring only authenticated users and devices can connect. This episode explains how 802.1X works as a port-based network access control mechanism, acting as the foundation for many secure wireless and wired deployments. You’ll learn about the three roles in 802.1X: the supplicant (client), the authenticator (switch or access point), and the authentication server (typically RADIUS).

We also dive into the Extensible Authentication Protocol (EAP), which provides flexibility by supporting various authentication methods such as EAP-TLS (certificate-based), EAP-PEAP (password-based), and EAP-TTLS. This episode is essential for understanding how network security extends all the way to the edge, particularly in BYOD and guest access scenarios. It’s a must-know topic for both the exam and real-world configuration.

Centralized authentication simplifies user management while enhancing security. In this episode, we compare two core protocols—TACACS+ and RADIUS—and explain their roles in authenticating access to network infrastructure devices. You’ll learn how TACACS+ provides command-level control and full separation of authentication, authorization, and accounting, while RADIUS is more common in end-user access scenarios like VPNs and wireless login.

We also explore Single Sign-On (SSO) systems and directory services like Active Directory and LDAP. These systems allow users to log in once and gain access to multiple services, reducing password fatigue and enabling centralized enforcement of security policies. Centralized authentication is critical for scalable IT environments, and understanding it prepares you for everything from infrastructure hardening to enterprise onboarding.

Beyond basic firewalls and access controls, advanced security mechanisms offer deeper visibility and proactive defense. In this episode, we explore Network Access Control (NAC), a system that evaluates a device’s health and compliance status before granting access to the network. NAC solutions can quarantine non-compliant systems, require updates, or redirect them to remediation zones. We explain how 802.1X, RADIUS, and posture assessments enable these capabilities.

We also cover honeypots—decoy systems designed to lure attackers away from critical assets—and how they help in threat detection, analysis, and even legal investigations. Finally, we review different authentication models like federated identity, SSO (Single Sign-On), and token-based systems used in modern enterprise environments. This episode showcases the tools and concepts that go beyond the basics and into adaptive, context-aware security design.

Zero Trust networking flips the traditional perimeter-based security model on its head. In this episode, we unpack the Zero Trust principle of “never trust, always verify,” and explore how it applies to network design. You’ll learn how Zero Trust assumes breach by default and demands continuous authentication, authorization, and monitoring regardless of whether a user or device is internal or external. We explain how technologies like microsegmentation, MFA, and identity-based policies enforce this model.

We also discuss how Zero Trust fits within a broader Defense in Depth (DiD) strategy. Defense in Depth layers multiple security controls—technical, administrative, and physical—to ensure that if one fails, others still protect the network. We examine how firewalls, endpoint security, access controls, and user training work together to form a comprehensive security architecture. This episode provides a strategic framework for designing layered, modern security systems.

Security in networking isn’t just about blocking attacks—it’s about minimizing exposure by limiting what users and systems can access. In this episode, we examine the Principle of Least Privilege (PoLP), which states that users should have only the access they need to perform their duties—no more, no less. You’ll learn how this concept applies not only to user accounts but also to devices, applications, and even services within the network. Limiting privilege helps reduce the damage caused by accidental changes or compromised accounts.

We also explore Role-Based Access Control (RBAC), a structured way of applying least privilege across departments, job functions, and user groups. We cover the differences between role-based and discretionary models, how RBAC integrates with Active Directory and network devices, and why it’s a common requirement in audits and compliance frameworks. This episode is vital for understanding how to implement logical controls and maintain secure boundaries between users and systems.

This episode dives into the foundational security concepts of vulnerabilities, exploits, and exposures—terms that appear throughout the Network Plus exam and underpin much of what cybersecurity involves. We begin by defining what constitutes a vulnerability, whether it’s a flaw in software, a misconfiguration in hardware, or a weakness in protocol design. From there, we explain what an exploit is: the method by which attackers take advantage of a vulnerability. Finally, we clarify what it means for a system to be exposed, especially when vulnerabilities are present without adequate controls in place.

These concepts are central to understanding the nature of risk in network environments. You’ll gain the clarity needed to distinguish between potential weaknesses, active attack methods, and the conditions that create exposure to threats. This episode also helps you recognize how these ideas apply to patch management, threat modeling, and the overall goals of network defense. By the end, you’ll be able to identify vulnerability types and understand how exploits are used to compromise systems—critical knowledge for both the certification and real-world scenarios.

Every security strategy begins with the CIA Triad—Confidentiality, Integrity, and Availability. In this episode, we explore how these three principles guide all security policies and how various threats can undermine each one. Confidentiality threats include unauthorized access and data breaches. Integrity threats involve tampering, spoofing, or unauthorized changes. Availability threats include DDoS attacks and hardware failures that block access.

We also categorize threat types including malware, phishing, insider threats, and zero-day exploits. Each is mapped to the part of the triad it threatens, helping you understand how and where to apply protective controls. This episode lays the philosophical and practical foundation for every security decision you’ll make.

Domain 4 marks a transition from availability and performance into security—protecting the integrity and confidentiality of the network. In this episode, we introduce the core topics that make up Network Security, including authentication, access control, attack types, and hardening techniques. The goal of this domain is to teach you how to prevent, detect, and respond to threats at every layer of the OSI model.

You’ll also get an overview of best practices and security frameworks used in enterprise environments, from Zero Trust to NIST and CIS controls. Security isn’t just a checkbox—it’s an ongoing mindset that touches every part of your infrastructure. This introduction sets the stage for understanding what it takes to build and maintain secure networks.

Configuration data is as critical as hardware—and losing it can lead to hours of downtime. In this episode, we walk through backup and restore procedures for routers, switches, firewalls, and other network appliances. You’ll learn how to use TFTP, FTP, or USB-based methods to copy and store configurations, and how to schedule automated backups using cron jobs or built-in tools.

We also cover best practices for labeling, versioning, and testing restores before you need them in a crisis. Backups aren’t just about recovery—they’re also useful for auditing, documenting changes, and rolling back failed upgrades. This episode prepares you to protect your configs as diligently as your hardware.

Routers are essential gateways, and if one fails, the network can grind to a halt—unless redundancy is in place. This episode explores VRRP (Virtual Router Redundancy Protocol) and other First Hop Redundancy Protocols (FHRPs) that allow multiple routers to share the same virtual IP address. You’ll learn how a “master” router handles active traffic while backups wait to take over seamlessly in the event of failure.

We walk through the election process, priority configuration, and preemption settings that determine which router takes the lead. These protocols are vital for enterprise networks that require uninterrupted gateway access. Whether you're building a resilient core network or preparing for exam scenarios involving router failure, this episode teaches you how virtual gateways provide true fault tolerance.