Every year, thousands of cyberattacks occur all across the world. In 2021, some of the most notorious cybersecurity breaches included the following:

  • DarkSide’s attack on Colonial Pipeline, which involved shutting down a fuel supply line feeding the East Coast and ransom demand of $4.4 million.
  • Russian ransomware-as-a-service group REvil’s deployment of a malicious hotfix containing a ransomware payload, targeting Kaseya VSA – a software popularly used for remote network management.
  • Again, the same organization (REvil) launched an attack against Quanta – an exclusive supplier to Apple Inc., with a $50 million ransom.

While the aforementioned events were launched against big businesses, companies of all sizes are under threat of being targeted by cybercriminals, so no one is truly safe from cyberattacks.

And with a lot of companies conducting their business online, the internet has become a free-for-all menu for unscrupulous individuals and groups. These cybercriminals target companies by exploiting vulnerabilities the moment they spot them.

If you’re a business owner, it’s highly likely you already have a network security system in place. But is it enough?

To fortify your defenses online, you might want to consider adopting a defense-in-depth (DiD) strategy.

The Defense-in-Depth Strategy

Defense in depth (DiD) is a cybersecurity strategy that layers a succession of defensive techniques to protect sensitive data and information.

In the event that a security control fails or a vulnerability is exploited, DiD provides several redundant protective measures. This multi-layered method with deliberate redundancy improves overall system security and handles a variety of attack vectors. Basically, with a defense-in-depth strategy, a bad actor who breaches one layer of defense may still get contained in other security layers.

It comes from the same-named military strategy conceived in the United States, which aims to stall an attack rather than defeat it with a single strong line of resistance.

And because it resembles the layered defenses of a medieval castle in principle, DiD is sometimes referred to as the “castle strategy.” The redundant protective controls function like the moat, ramparts, drawbridge, towers, battlements, and other obstacles of a castle that must be overcome before a breach is complete.

End-user security, product design, and network security are all examples of defense-in-depth cybersecurity use cases.

Modern Cybersecurity Challenges

The digital age has changed how people live, work, and play. Ironically, the digital world we live in is always vulnerable to hacking and other forms of cybercriminal activities. And because there are so many possible attackers, it’s crucial to have adequate security in place to protect our systems and networks.

Sadly, there is no single approach that can adequately defend a network or system against all types of cyberattacks and protect it from these common loopholes in cybersecurity strategies:

  • It takes far too long to locate viruses or identify malware.
  • Employees are targeted for phishing scams meant to expose networks to attacks.
  • Updates are underappreciated and usually ignored, and known weaknesses are not patched in time.
  • Employees and users do not fully understand or are not aware of their key role in enforcing security regulations.
  • Encryption is either absent or poorly implemented.
  • Malware protection is inadequate or lacking.
  • Work-from-home policies are bringing new risks for remote workers who connect to insecure networks and inadvertently expose sensitive information.
  • Security issues can exist in certain physical systems and structures, like inadequate access control to company premises and facilities.
  • The security of business partners or supply chains is not always guaranteed.

Large cloud service providers have excellent security and established systems in place, but they are only as safe as their workers and users make them. Users are frequently the victims of internet phishing scams and harmful links designed to expose networks to thieves scanning the internet for sensitive data they can exploit.

Users don’t require an employee credential or a unique business device to access data in the cloud, and it usually takes only a few simple clicks for your network to be exposed to threats lurking on the internet. This is where the defense-in-depth strategy comes in handy.

How Defense in Depth Works

All levels of IT systems can benefit from a multi-layer security approach. Defense in depth can drastically improve your security profile – whether it’s a single laptop accessing the internet from a coffee shop or a major company with thousands of users or employees.

These days, a single layer of protection can never adequately safeguard an enterprise. Where one door may be shut, others will be left wide open, and hackers are always ready to rapidly exploit such vulnerabilities.

When you combine a variety of measures as part of your multi-layer security – including data encryption, firewalls, integrity auditing solutions, intrusion detection systems, and malware scanners – you can successfully plug those loopholes that result from depending on only a single security solution.

Elements of a Defense-in-Depth System

In a defense-in-depth system, the multi-tiered approach to security comprises features from the following elements:

  • Data: Files, data, or information is stored in a database, virtual machine disks, SaaS applications like Office 365, and on the cloud.
  • Applications: Software applications must be secure and free from flaws. Sensitive app information should be stored in a secure storage medium, and security has to be a design requirement for all application development.
  • Compute: Manage access to virtual machines for security, apply endpoint protection, and keep all systems patched and current.
  • Networking: Keep communication between resources to a minimum. Deny access by default, restrict inbound and outbound internet access, and secure all on-premises networks.
  • Perimeter: Filter large-scale attacks with distributed denial of service (DDoS) prevention. Use perimeter firewalls to detect and alert you to dangerous network attacks.
  • Access and identity: Ensure you control infrastructure access and change. Implement single sign-on and multi-factor authentication, as well as conduct change and event audits.
  • Physical safety and security: A company’s first line of defense is ensuring physical building security and access control to computing hardware within the data center.


How Defense in Depth Helps

Most businesses know that a single layer of protection or a single point product (e.g., a firewall) is insufficient to defend them from today’s sophisticated cyber thieves.

If a hacker successfully infiltrates an organization’s network, for example, defense in depth allows managers to activate countermeasures in time.

You can reduce the risk of a security breach by stacking and even duplicating certain processes. Although on the surface, this security redundancy may appear to be inefficient, a defense-in-depth strategy can ward off threats effectively because if one security product fails, another is ready to take over.

The elements below serve as critical security layers in a defense-in-depth approach as companies grow as well as the number of devices, applications, and services they employ:

  • Data loss prevention
  • Encryption
  • Endpoint detection and response (EDR)
  • Intrusion detection and prevention systems
  • Network segmentation
  • Two-factor authentication (2FA) or multi-factor authentication (MFA)
  • VPNs

How Softlanding Can Help With Your Multi-Layered Security Approach

Many organizations rely on Microsoft product security features to keep their email and data safe. This is why Microsoft resources, products, and services – including Microsoft 365 and Azure – are designed with defense in depth in mind.

Companies that utilize a layered approach, such as defense in depth, are more confident in their capacity to prevent cyberattacks and are less likely to suffer severe consequences if one does occur.

If you require assistance in integrating a defense-in-depth strategy together with the Microsoft technology you currently use, please get in touch with Softlanding. We are your source for IT security managed services.

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Softlanding is a long-established IT services provider of transformation, professional services and managed IT services that helps organizations boost innovation and drive business value. We are a multi-award-winning Microsoft Gold Partner with 13 Gold Competencies and we use our experience and expertise to be a trusted advisor to our clients. Headquartered in Vancouver, BC, we have staff and offices in Toronto, Montreal and Calgary to serve clients across Canada.

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