What Is Network Security?

A firewall is a device that monitors, filters, and controls incoming and outgoing network traffic based on predefined security rules. Acting as a barrier between trusted internal and untrusted external networks, it works by inspecting data packets and choosing to block or allow them.

For example, a financial institution might configure its firewall to block traffic coming from unauthorized IP addresses while still allowing legitimate traffic to pass through. This mitigates a potential breach without interrupting core operations.

Next-Generation Firewall (NGFW) is a modern iteration that goes beyond traditional solutions, incorporating deeper packet inspection for more robust protection. NGFWs often package many essential network security capabilities into one comprehensive offering, including intrusion prevention, antivirus and file sandboxing, web and DNS filtering, and more.

With a hybrid mesh architecture — firewall’s next evolution — organizations can centralize control and visibility of formerly disparate tools. This makes it easier to coordinate and control policies across on-premise and cloud-based firewalls, not to mention multiple branches and campus locations.

Intrusion prevention systems detect and block known and suspected threats before they can impact the network core or devices at its edge. In addition to north/south and east/west deep packet inspection, including inspection of encrypted traffic, they can also provide virtual patching, which mitigates vulnerabilities at the network level.

Using an IPS, organizations can rapidly detect attack signatures and abnormal behavior. The system automatically takes action to block malicious traffic while alerting administrators for further investigation.

Antivirus and sandboxing tools are key to determining whether a file is malicious. While antivirus blocks known malware threats, sandboxing provides a safe environment to analyze suspicious files.

Let’s say a user downloads a file from an email attachment. The antivirus software scans it for known attack signatures and behaviors. If it’s a confirmed threat, the software quarantines or removes the file. For an unknown file, sandboxing isolates it into a protected space where it can be tested to determine if it’s malicious.

Some security vendors are leveraging these capabilities in concert with AI, allowing them to perform sub-second analysis of never-before-seen threats.

Domain Name System (DNS) filtering allows organizations to stop domain-based attacks, such as DNS hijacking, tunneling, etc. Likewise, URL filtering prevents users and applications from accessing suspicious URLs, which could be linked to malicious websites. These web security tools help enterprises enforce acceptable-use policies while protecting them from harmful content.

For instance, if a user attempts to access a malicious website, the web filter checks its database of categorized sites. If the domain has been flagged, it’ll block access entirely.

Some firewall solutions now include Cyber Asset Attack Surface Management tools that can help organizations automatically identify network IT, OT, and IoT assets, and assess those assets for potential risks. The tools can also assess existing security infrastructure and controls for misconfigurations and less-than-optimal settings that can then be updated to strengthen an organization’s security posture.

Remote access VPNs allow users to securely access the corporate network from outside their organization’s office. They create a private, encrypted connection from a public Wi-Fi network, enabling employees to safely use critical resources from their personal devices regardless of location.

These solutions are especially useful in hybrid work environments, allowing remote workers to stay productive with the assurance their data is safe from malicious interception.

Network access control governs access to the network, ensuring that only authorized and compliant devices gain entry. NAC solutions identify and authenticate devices, granting access only if they meet predefined compliance policies.

For example, enterprises might configure their NAC to block certain device types. This prevents users from accessing the network on unprotected personal devices, but it also can help the company manage IoT and operational technology (OT) deployments.

Hardware that fails to meet the criteria may be quarantined, redirected to a remediation network, or denied entirely.

Although not directly supporting the network, there are related cybersecurity technologies that help protect the infrastructure:

Endpoint detection and response (EDR) security solutions continuously monitor all user and endpoint activities to protect them from threats and detect suspicious behavior. They also offer investigation and incident response capabilities, which eradicate the threat and isolate the affected system from impacting the rest of the network.

Email security protects employees from cyber threats and social engineering attacks, including phishing, spear-phishing, and other email-based tactics. It works by examining inbound email to detect potential risk factors. For instance, it can identify communications that contain malware, suspicious links, questionable content and imagery, and other abnormalities — blocking the email from reaching the user’s inbox.

DLP solutions identify sensitive information throughout cloud systems, mitigate accidental data sharing, and prevent data exfiltration. They increase visibility into data stores, helping enterprises track and remediate policy violations, thereby improving internal compliance.

DDoS protection defends against denial-of-service attacks, which aim to overwhelm the corporate network and disrupt operations. FortiDDoS, for example, rapidly inspects data packets and automatically blocks illegitimate traffic from flooding the network.

Application security tools allow administrators to recognize traffic generated by well-known and custom applications. Using IPS protocol decoders, it analyzes traffic to identify applications, enabling admins to quickly form policies to allow, deny, or restrict access to specific apps or entire categories of them. This optimizes bandwidth utilization while also mitigating malware, unauthorized file transfers, and other risks.

CASB solutions provide security to software-as-a-service (SaaS) applications, users, and data. Inline CASB offers visibility, compliance, and threat protection for data in motion and at rest in cloud apps, but also creates shadow IT reports, risk assessments, and more.

Application programming interfaces (APIs) allow open-architecture CASBs to directly integrate with SaaS providers. This enables admins to scan cloud configurations, ensuring their users are monitored and protected no matter what device they’re using.

Network security in inherently more complex in larger, more complicated IT environments. Fortunately, there are several solutions fit for network protection at scale:

Modern security operations centers (SOC) require a centralized approach to event management. Without it, they lack the context or visibility to protect the organization effectively.

SIEM solutions provide a unified view of security across the enterprise, collecting information from network, endpoint, cloud, and other security products. They also offer behavior-based AI-powered threat detection, investigation, compliance reporting, and more. In short, SIEM reduces the complexity of managing network and security operations.

NDR monitors internal network traffic, baselining normal behaviors and using machine learning (ML) and other analytics to detect malware, malicious traffic, and abnormal patterns that may indicate an attacker within the network. It also provides a robust capability to investigate and take immediate action on verified alerts.

XDR streamlines threat detection and response across an enterprise's security ecosystem. By consolidating data from endpoints, networks, emails, and the cloud, it identifies and links suspicious activities that individual tools might miss. This integrated approach enables quick investigation and remediation of alerts or multi-step incidents through automated and manual actions. Leveraging endpoint detection and response (EDR) capabilities, XDR provides endpoint agents, telemetry, and endpoint blocking to effectively manage challenges while enhancing threat detection and response capabilities.

 The progression from endpoint detection and response (EDR) to managed detection and response (MDR) to extended detection and response (XDR) follows the path of digital acceleration with ever-expanding attack surfaces and a hybrid workforce.

Essentially, the difference between EDR, MDR, and XDR are as follows:

• EDR: Endpoint Detection and Response acts like an alarm system for an organization. When it detects a threat at an endpoint, it immediately alerts the company.
• MDR: Managed Detection and Response is a security approach that focuses on individuals and their behaviors. It prioritizes endpoint protection.
• XDR: Extended Detection and Response takes MDR to the next level with a software-based practice that protects an enterprise's entire infrastructure.

Today, network edges are anywhere the user connects and businesses may not be able to extend security everywhere it’s needed. Managed security service providers (MSSPs) can help fill the gap with the critical expertise and infrastructure required immediately, at less cost.

For example, a managed detection and response (MDR) service can be a great choice for SMBs that need enterprise-grade threat monitoring and response but find it too expensive to build or staff internally.

Larger organizations who need more comprehensive protection of a distributed environment and don’t have the resources in house, can choose an XDR service for cross-layered detection and response. XDR collects, normalizes, and then correlates data over a variety of security layers, including endpoints, firewalls, email, servers, cloud workloads, and the general network. 

MDR is a fully managed threat detection and response service delivered by an outsourced MSSP. With MDR services, security teams can enhance their ability to rapidly detect, investigate, and respond to unauthorized and/or suspicious activity. Some MDR services also offer threat hunting and recommendations for improving overall security posture.

Some MSSPs also extend MDR with XDR which monitors, detects and analyzes security signals across endpoints, network, cloud, SIEM and email security systems. XDR is a new, alternative approach to traditional detection and incident response, integrating detection and response procedures across multiple environments to reduce the mean time to detect and repair attacks.

XDR is a natural extension of EDR suitable for organizations that have complex IT environments or are highly vulnerable to cyberattacks. XDR is highly scalable, supports multiple data sources, and ensures end-to-end protection of an organization’s attack surfaces.

A typical in-house security operations center (SOC) requires a dedicated staff of security engineers and analysts and the tools to support their work. The high cost of running a SOC in house compounded by the shortage of cybersecurity talent and the burnout that often transpires, leads many organizations to choose a managed SOC-as-a-Service (SOCaaS). This allows them to outsource threat hunting, monitoring, detection, and remediation to an MDR or MXDR service provider with the cybersecurity experience,  infrastructure, and tools, to actively monitor customers’ threat surfaces 24/7.

Cloud security is a shared responsibility. In general, the public cloud infrastructure is secured by the service provider—such as AWS, Azure, or GCP—and the workloads running on the infrastructure are secured by the customer. To meet the business imperative of cloud migration, organizations need a network security solution in the cloud that offers advanced protection, flexibility, and predictable costs.

However, organizations that are accelerating their cloud adoption may not have the resources, skills, or time to build, scale, or adapt their cloud security to meet the pace of their business. A managed firewall service allows organizations to offload cloud security infrastructure maintenance, get deep visibility, apply robust controls, and optimize cloud security spend.

A cloud-native, managed firewall service removes the heavy lifting around network security operations and provides a frictionless experience to help customers easily deploy enterprise-grade security on the public cloud.

Cloud migration requires organizations to secure key cloud services. A next-generation, managed firewall service or network Firewall-as-a-Service (FWaaS)  simplifies security management with full visibility across environments and broad protection across cloud workloads and applications.

Whether a managed firewall service or a network FWaaS, it is critical that organizations ensure that their public cloud workloads are protected by next-generation security solutions powered by comprehensive threat intelligence.