How Layered Security Can Protect Your Network

Layered security entails using multiple security controls in tandem to protect a network. Also known as defense-in-depth, each security layer makes breaching the system exponentially more difficult, as hackers must penetrate each layer in order to succeed.

 Without layered security, attackers only have to navigate a limited number of safeguards designed to prevent intrusion. As a result, it’s easier for them to gain entry, particularly if they can exploit an existing vulnerability gain immediate access.

Each security layer increases the overall penetration difficulty, making systems harder to breach. Plus, it creates more opportunities for potential intrusion detection, allowing companies to take action before their network is compromised.

Often, the components of a layered security approach are designed to counteract any existing shortcomings or flaws relating to the other layers. By using the strategies together, you effectively reinforce your overall approach to security, ensuring a weakness in one area is overcome by the strength of another.

Layered security approaches can involve a wide array of security controls and components. Below, we’ll provide an overview of some of the most common ones used for layered security.

Components of Layered Security


A firewall is often viewed as the first line of defense. It allows companies to control and monitor network traffic, enforcing rules designed to keep unauthorized parties from reaching key systems. Essentially, the firewall acts as a barrier, ensuring only trusted traffic is able to move freely into and across the network.

Antivirus and Antimalware Software

One of the quickest ways to circumvent many security solutions is through the introduction of viruses and malware. Often, these malicious programs can make any obstacles that would otherwise prevent an attacker from gaining entry insufficient, as the virus or malware can create an opening that otherwise didn’t exist.

Ideally, antivirus and antimalware software should be viewed as a foundational component of network security. By choosing robust options and ensuring they remain up-to-date, you reduce the odds of a malicious application allowing hackers to access your network or other critical systems.

Physical Security

When many companies think about network security, they focus on technology-related risks. However, safeguarding your physical systems is an essential part of the equation. By ensuring unauthorized personnel can’t access or interact with critical systems, servers, and other devices, you reduce the odds that infrastructure and physical components are compromised.

Often, the best approach is to ensure that servers and similar infrastructure components are in a separate, secured area. That allows you to prevent access by anyone other than the employees who have a legitimate work-related need to engage with the equipment.

However, also securing other parts of your office or building is wise, as that prevents unauthorized individuals from getting access to any networked devices on the premises. With security cameras, guards, fences, and other measures, you can create a strong security perimeter to protect the premises against unwanted intruders.

Multi-Factor Authentication

When systems are only protected by user login credentials, they’re often far more vulnerable than many organizations expect. Compromised credentials occur with surprising regularity, particularly since it isn’t uncommon to rely on the same email addresses and passwords across several systems or services. Additionally, social engineering and phishing attacks may lead employees to disclose their login credentials believing they were provided to a legitimate site, person, or entity.

Multi-factor authentication helps overcome the shortcomings of traditional login credentials. It requires a second step when a person attempts to access the network, such as a one-time code delivered via text message. With that process, an email address and password combination – even if correct – is insufficient to gain entry, making your systems more secure.

Patch Management

In many cases, software applications are released under the belief that they are fully secure. However, as time passes, vulnerabilities are commonly identified. When they’re found, patches – minor updates to the application – address those shortcomings, ensuring they can’t be exploited by attackers who want to gain entry into systems.

Often, patches also address other potential issues with software and firmware. For example, they may improve performance or correct bugs, improving the end-user experience. As a result, it’s wise to create a patch management strategy to ensure they’re implemented as quickly as possible.

Access Controls

Generally speaking, employees should only have access to systems and tools that are genuinely required for their job. By using administrative options to block specific employees from accessing unnecessary systems – essentially limiting the capabilities of their login credentials – you reduce overall risk.

With robust access controls, even if a hacker gains access to an employee’s credentials, they can’t automatically access every networked system. Instead, they’ll encounter other security measures that block them from those areas, potentially reducing the scope of the attack.

Along with limiting access for existing employees, it’s critical to delete credentials relating to employees that are no longer with the company. Additionally, if a worker transitions into a new role, it’s wise to review their current level of access, ensuring it’s appropriately adjusted based on their new function.

Intrusion Detection and Activity Monitoring Tools

When an attacker attempts to access a company system, they may use techniques that result in abnormal network activity. For instance, there may be repeated failed login attempts or login activities occurring at odd times of the day. Similarly, if a hacker penetrates your security and reaches your network, they may take actions that differ from those that commonly occur in your organization.

By using intrusion detection and activity monitoring tools, companies can learn about suspicious activities faster. This allows the designated IT team members to take immediate action, determining whether the activity is related to an attack or if specific steps need to be taken to ensure the network is appropriately protected.

Email Filtering

Malicious links and files delivered via email are common initial entry points for attackers. By using email filtering technologies that redirect potentially malicious messages at the gateway, you can reduce employee exposure to potentially harmful emails.

Even if the emails head to a spam folder or similar spot, allowing employees to review them to ensure a legitimate message wasn’t accidentally miscategorized, moving the message to those areas serves as a red flag. Plus, companies can implement other protocols, such as preventing link clicking or attachment downloads from emails sent to those folders, reducing the odds of accidental interaction.

Endpoint Protection

Any device that connects to your network can potentially be used as an entry point by attackers. By implementing strong endpoint protection across all connected devices, it’s far more challenging for hackers to gain access.

Ideally, you want to secure every device type. Beyond computers and laptops, examine mobile devices, networked printers, smart devices, security cameras, and anything else that has a connection, as they can all represent potential entry points.

VPNs and Other Remote Work Security Tools

During COVID-19, many companies had to quickly adjust their processes to support remote work. In some cases, this led to quick decisions that weren’t always security-oriented.

Now that the worst of the pandemic has passed, companies should review their remote work technologies to ensure they’re appropriately secure. Additionally, they should update policies and implement beneficial technologies to reduce overall risk.

One classic example of a key telecommuting technology is VPN. With VPN, employees have an encrypted, secure connection, as it creates a private tunnel for accessing company systems and data. However, this isn’t the only option available, so companies should explore the various technologies to determine which ones are the best fit for their needs.

Web Content Restrictions

Preventing employees from accessing high-risk websites from browsers on company computers reduces overall exposure to various threats. Whether a site is a known risk or a potential threat, these technologies steer employees away from potentially harmful options. As a result, they’re less likely to incidentally download viruses or malware or encounter phishing, effectively preventing a range of security incidents.

Complex Password Policies

Requiring complex passwords helps prevent brute force attacks that can allow hackers to gain entry to your network. When there are more total characters and minimum requirements for different character types – such as requiring numbers or symbols – it enhances overall security.

If you use that in conjunction with rules that require new passwords at set intervals and prevents password reuse for a specific period, the approach is even more effective. Even if a previous password is compromised, once it’s no longer valid (or allowed), the risk is greatly minimized.

Dark Web Monitoring

When hackers gain access to login credentials, some may decide to attempt to sell the information to others or publish the data openly on the dark web. By using the correct monitoring tools, you can regularly scan the dark web for information relating to your company, including potentially compromised email and password combinations.

If any user credentials are found, you can take steps to reduce the risk. For example, you could require an immediate password change, as well as block the employee from reusing that password in the future.

Employee Training

Employee training is a critical component of layered security. It teaches your workforce to identify risks, ensuring they can spot malicious emails, risky websites, phishing calls, and more. Plus, it allows you to instruct employees about what to do should they encounter a malicious email or other potential security threat, ensuring incidents are reported, that dangerous emails are deleted, websites are appropriately blocked, and information is provided to the proper authorities as needed.

In most cases, security training should occur relatively regularly. Along with requiring the course as part of the new hire onboarding process, make annual refreshers mandatory. That not only keeps security fresh in everyone’s mind; it also creates opportunities to inform your workforce about new, emerging threats, ensuring they’re prepared for the latest techniques.

Backup and Disaster Recovery Protocols

While the goal is typically to avoid an attack, even robust security strategies aren’t foolproof. As a result, companies should have a clear plan for backing up company data and supporting disaster recovery should the worst-case scenario occur.

Backups and disaster recovery plans allow companies to reestablish operations and restore data after a cyberattack does damage. Just make sure that backups are appropriately secured and encrypted and that any disaster recovery plans are reviewed and tested regularly. That way, should quick action be necessary, your company is ready.

About the Author

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Catherine Reed

Catherine Reed is a writer and researcher with experience writing about a wide variety of topics including personal finance, technology, and staffing.