What is Network Security? A Comprehensive Overview

Network security is the practice of identifying, preventing, and remediating threats within the enterprise network. Since the majority of cyberattacks occur over the network, monitoring and defending the corporate network is essential to minimize the cost and impact of cyberattacks on the organization.

At a high level, the key goals of network security are the same as for all other areas of cybersecurity: ensuring confidentiality, integrity, and availability. A network security architecture and strategy must have processes and security controls in place to ensure each of these.

Types of Network Security Tools and Technologies

A network security architecture should be customized to a company’s unique network environment and security needs. However, some key solutions appear in the majority of network security infrastructures, including the following:

Firewalls

Firewalls are network security solutions that define a network boundary that protects against unauthorized access to internal resources. All traffic crossing the network boundary passes through the firewall, which inspects and determines whether to allow or block it.

Firewalls have evolved significantly over time from stateless firewalls to modern next-generation firewalls (NGFWs). The original stateless firewalls performed simple packet inspection and made decisions based on source/destination IP addresses and port numbers. Stateful firewalls maintained data about the current status of a network connection, enabling it to identify packets that were invalid in context.

NGFWs integrate advanced security capabilities, perform deep packet inspection, and incorporate intrusion detection and prevention systems (IDPS) and other security capabilities, enabling them to identify and block malware, visits to unauthorized URLs, and other threats.

Network access control (NAC)

Network access control (NAC) solutions manage access to the corporate network. When a NAC receives a connection request, it evaluates it based on both the user and the device.

NACs can apply role-based access control (RBAC) policies and assess the security posture of the connecting device when making an access decision. This analysis may be performed when the device first connects to the network and when it attempts to access resources across network boundaries in a segmented network.

Intrusion detection and prevention systems (IDPS)

An intrusion detection and prevention system (IDPS) provides protection against various attacks, including brute force password guessing, distributed denial of service (DDoS) attacks, and exploits of vulnerable applications. They also leverage artificial intelligence and machine learning (AI/ML) to more accurately identify zero-day exploits and novel attack campaigns.

IDS and IPS systems differ in their responses to an identified threat. An IDS is designed to simply alert the security team of an attack but allows it to pass through. An IPS, on the other hand, will block suspected attacks, providing greater security at the cost of potentially blocking legitimate traffic.

Virtual private networks (VPNs)

Virtual private networks (VPNs) offer secure remote access and are deployed in one of two ways: Site-to-site VPNs that are designed to connect two geographically distributed locations over an untrusted network, such as the public Internet, and remote access VPNs to securely connect remote workers to the corporate network and its applications and data. VPNs create an encrypted tunnel that allows all network traffic flow through, protecting it against eavesdropping and other potential threats.

VPNs allow remote access to corporate environments but lack any built-in access controls, providing unrestricted access to company networks and IT resources.

Zero trust network access (ZTNA)

Zero trust network access (ZTNA) solutions provide an alternative to VPNs and implements least privilege access controls and explicit verification for both remote and on-prem workers. Companies can granularly control access to the network, applications, and data, providing additional protection against compromised accounts.

Email security

Email is one of the biggest security threats that companies face. Many cyberattacks begin with a phishing email, which can deliver malware or attempt to steal users’ login credentials. An email security strategy should include both technical and non-technical defenses. Email security solutions should offer spam filtering, sandbox malware analysis, and other email security techniques to identify and block malicious emails.

Email security should be incorporated into cybersecurity awareness programs geared toward educating users on security best practices. This should include avoiding clicking on links in emails, being wary of suspicious attachments, and validating the identity of an email’s sender before trusting its links or attachments.

Web security

Web security solutions protect employees browsing the Internet from web-based threats. These complement SSL/TLS encryption which protects against eavesdropping and man-in-the-middle (MitM) attacks as web traffic travels over untrusted networks.

Secure web gateways (SWGs) are critical components of a web security architecture. Traffic passing through the SWG is inspected and filtered to identify and block traffic to malicious websites. Additionally, SWGs can help enforce corporate security policies by preventing users from browsing to sites that are not approved by the organization.

Secure access service edge (SASE)

Secure access service edge (SASE) converges networking and security functionality into a single, cloud-native service. Integrated software-defined WAN (SD-WAN) functionality optimally routes traffic over the corporate WAN, and each SASE point of presence (PoP) includes a range of security solutions to monitor, filter, and secure network traffic.

SASE’s cloud-native design and converged security are intended to address the main security challenges faced by the modern business. As a growing percentage of corporate IT assets move to cloud environments, companies need solutions that can be natively deployed and offer protection in the cloud. SASE converges several key cloud security capabilities, including cloud access security broker (CASB), firewall as a service (FWaaS), and ZTNA.

Data loss prevention (DLP)

Data breaches are among the most expensive and damaging cyberattacks a company can face. A successful data breach can result in expensive recovery, brand damage, and legal and regulatory penalties.

Data loss prevention (DLP) solutions help companies protect against data breaches by restricting the flow of sensitive data outside of the corporate network. They scan network traffic for known sensitive data (such as payment card numbers) and ensure that it isn’t transmitted to unauthorized parties.

Developing a Comprehensive Network Security Strategy

A corporate network security strategy should be designed to meet business needs and address the company’s biggest security risks. Some best practices for designing and implementing a comprehensive network security strategy include the following:

• Risk Assessment: The first step in creating or updating a corporate network security strategy is identifying security gaps. The organization should perform a comprehensive risk assessment to identify current vulnerabilities and any visibility and security gaps that may exist in corporate security controls and processes.
• Policy Creation: After identifying potential control and policy gaps, the company can define policies to address these issues. For example, an organization allowing BYOD should have a policy in place that defines acceptable use of corporate resources and required security controls for devices used for work.
• Employee Education: Many cyberattacks are caused by employee errors Training and educating employees on security best practices can aid in avoiding errors or actions that place the company at risk.
• Incident Response: After a security incident, a quick, correct response is vital to minimize the impact on the organization. Companies should have an incident response plan and team in place to minimize disruption and the costs of an intrusion.
• Defense in Depth: Relying on a single security solution leaves the organization vulnerable if it fails to detect or block attacks. A network security architecture should be built around a framework that supports a layered, defense-in-depth approach.

Network Security in the Era of Remote Work and Cloud

IT networks and network security have changed significantly in the last five years. The rise of remote work and cloud computing has introduced new security challenges for companies. Some key security best practices include:

• Secure Remote Access: Secure remote access is essential to protecting remote users’ traffic against eavesdropping and corporate resources against unauthorized access. Organizations should use a remote access solution — such as ZTNA — that offers traffic encryption and managed access to corporate resources.
• Cloud Configurations: Cloud security misconfigurations are a common cause of security incidents, especially in complex multi-cloud environments. Organizations require security solutions that enable them to consistently extend and enforce security controls to cloud environments.
• Consistent Visibility: Multi-cloud environments can be difficult to monitor and manage due to the variety of different platforms and available security controls. Achieving consistent visibility and control across on-prem and cloud environments requires security solutions that can operate across all parts of an organization’s IT infrastructure.
• Cloud-Specific Controls: Cloud environments face unique security risks due to microservices, SaaS solutions, and other cloud resources. Companies should deploy policies and security controls designed to manage the security challenges specific to these solutions, such as tainted images for containerized applications.

Metrics and KPIs for Measuring Network Security Effectiveness

Metrics are essential to evaluate the effectiveness of a security program and build a culture of continuous security improvement. Some key network security metrics to track include:

• Blocked Intrusion Attempts: How often do attackers target the company, and what percentage of those attacks are blocked?
• Number of Known Vulnerabilities: How many known, unmanaged vulnerabilities exist in corporate systems, and how has that number changed over time? How many are critical? How many are high-risk?
• Mean Time to Patch: What is the average time it takes the organization to patch a vulnerability? What about high or critical-severity vulnerabilities?
• Security-Related Downtime: What is the average amount of downtime experienced by corporate applications due to cyberattacks?
• Mean Time Between Failures: How frequently do corporate systems go down due to a cybersecurity incident?
• Mean Time to Detect: How long does it take the organization to detect an attempted attack?
• Mean Time to Remediation: What is the average time between the start of a security incident and its successful containment or remediation?
• Mean Time to Recovery: What is the average amount of time it takes to restore normal operations after a security incident?
• Cost Per Incident: How much does the average successful cyberattack cost the business in terms of lost revenue, productivity, legal fees, etc?
• Vendor Risk Exposure: How often do vendors issue patches for their products? How often do they suffer reportable security incidents?
• Regulatory Compliance: What percentage of regulatory requirements does the organization comply with?

The Future of Network Security: Emerging Threats and Technologies

Network security is a constantly evolving field. Some of the biggest emerging and future trends in the space include:

• AI Adoption: While AI is already used in many security tools, the technology’s increasing maturity will expand its footprint in the future. Adoption of AI for security offers enhanced detection of zero-day threats and faster, automated incident response.
• Edge Security: The growing adoption of Internet of Things (IoT) devices and edge computing creates additional security challenges. Network security architectures will increasingly include security tools deployed at the network edge to efficiently protect these devices.
• Zero Trust Adoption: While the zero trust security framework has existed for years, adoption is complex and time-consuming. As regulatory requirements and corporate security goals increasingly demand zero trust, it will become a core component of network security architectures.
• XDR Platforms: Extended detection and response (XDR) solutions offer enhanced threat detection and response capabilities. By aggregating logs and events from multiple security tools and employing AL/ML algorithms to detect threats faster, they offer more effective security protections.
• Blockchain-Based Security: Blockchain technology offers highly resilient and immutable digital ledgers and distributed computing systems. These capabilities can be highly valuable for security technologies that need a high degree of availability or a trustworthy log of events, such as access attempts and other potential signs of a security incident.

Ensuring comprehensive and consistent security

Network security is critical to success because it provides the opportunity to identify and address cyberattacks at scale before they pose a real threat to the organization. Corporate network security architectures should be designed to provide comprehensive and consistent security across on-prem and cloud environments.

As network security threats evolve, security leaders need to be proactive and adopt security solutions that will meet their needs today and in the future. Cato SASE Cloud offers cloud-native, converged security that unlocks consistent and usable protection across on-prem and cloud environments.