Certified: The Security+ Prepcast

In this episode, we’re looking at two critical components of modern infrastructure security: load balancers and sensors. Load balancers ensure that systems remain available and responsive, while sensors provide the visibility needed to detect, respond to, and recover from attacks. Both are foundational to building secure and resilient architectures.
Let’s begin with load balancer security. A load balancer distributes network or application traffic across multiple servers. The goal is to improve performance, ensure high availability, and maintain resilience in case of system failure. When a server goes down or reaches capacity, the load balancer reroutes traffic to healthy servers—keeping services online and responsive.
But load balancers also have security implications. One of the most important is SSL termination. This means the load balancer handles encryption and decryption instead of the backend servers. By offloading Secure Sockets Layer or Transport Layer Security operations, the load balancer reduces the processing burden on each server and centralizes certificate management.
This setup also enables inspection of encrypted traffic. If the load balancer terminates SSL connections, it can analyze the contents of that traffic for malware or policy violations before forwarding it to the backend systems. Without SSL termination, security tools can’t see what’s inside the encrypted sessions.
Another key feature of modern load balancers is DDoS protection. Some are equipped to absorb large volumes of traffic, detect anomalous patterns, and block malicious IPs. This is especially valuable in protecting web applications from volumetric attacks and application-layer floods. When paired with web application firewalls, load balancers help form a strong perimeter defense.
Load balancers must be configured carefully. Improper rules can expose internal IP addresses or allow unsafe failover behavior. Administrators should enforce secure session handling, review logs regularly, and segment traffic based on risk levels.
Now let’s turn to sensors. In security infrastructure, sensors are devices or software components that detect and report specific events or conditions. They form the foundation of monitoring systems and are used in everything from network security to environmental management.
There are several types of sensors you should know. Traffic sensors analyze network flows. These may be part of intrusion detection systems, NetFlow collectors, or SIEM inputs. They track packet rates, connection attempts, and protocol usage to identify potential threats or anomalies.
Intrusion detection sensors are specialized for identifying known attacks or suspicious behavior. They may monitor for signature matches, pattern anomalies, or rule violations. These sensors are often deployed at network ingress and egress points, or inside critical segments where lateral movement must be detected.
Environmental sensors monitor non-digital conditions that can impact security and availability. These include temperature, humidity, smoke, and vibration. In a data center, environmental sensors can trigger alerts if equipment is overheating, if airflow is blocked, or if physical tampering occurs. While not cybersecurity tools in the traditional sense, they are vital in protecting infrastructure from environmental threats and insider sabotage.
When deploying sensors, placement is critical. Network sensors should cover both north-south traffic—moving between zones—and east-west traffic—moving between internal systems. If a sensor only monitors traffic coming into the network, it may miss lateral movement after a breach.
Coverage and sensitivity must also be balanced. Too few sensors leave blind spots. Too many sensors—or improperly tuned ones—can overwhelm administrators with false positives. Sensor data must be normalized, filtered, and correlated using centralized tools like SIEM platforms.
Let’s look at a few real-world implementations. In one case, a manufacturing company deployed network sensors at the perimeter but neglected to monitor internal systems. When a workstation was compromised through a phishing email, the attacker moved laterally for days before being detected. After the incident, the company deployed additional sensors between business units and critical systems, improving their ability to detect internal threats.
In another case, a financial institution used traffic sensors and SSL termination on their load balancer to detect bot traffic targeting their online banking site. The attack involved repeated login attempts using stolen credentials. Because the load balancer could decrypt and inspect traffic, and because the sensors tracked session behavior, the attack was detected and stopped before accounts were compromised.
Environmental sensors also play a role. A data center experienced a rapid temperature spike after a cooling failure. Because sensors detected the change immediately, systems were shut down gracefully and hardware damage was avoided. This wasn’t just a facilities win—it was a security win, because system integrity and data availability were preserved.
As you prepare for the Security Plus exam, be ready to explain how load balancers contribute to both performance and security. Know what SSL termination is, how it supports traffic inspection, and how load balancers help absorb denial-of-service attacks. Understand the different types of sensors, their deployment strategies, and how they support visibility across the network and infrastructure. You may be asked to recommend sensor placement, choose between passive and active monitoring tools, or evaluate how traffic flows affect detection.