Preventing hacker attacks: “Never trust, always verify” as a security concept for the digital world.

achteckige Kästchen mit Schlössern, die globale Netzwerksicherheit darstellen sollen

Laptop mit Benutzername und Passwort, das für Cybersicherheitskonzept stehen sollWhat is Zero Trust?

Zero Trust Security is a security architecture in which each and every network access is regarded as insecure. Users and devices must always authenticate before access is granted. In addition, only encrypted communications are permitted.

In a nutshell, this model says: “Don’t trust anyone until they have been verified”.


How does the Zero Trust model work?

The Zero Trust policy is based on the “principle of least privilege”. All users (user identities) and applications must be authenticated and authorised. This means that they can only access the resources that they need to fulfil their tasks.

Authentication involves checking whether a user is actually who they claim to be. This is achieved, for example, by means of a user name and password, possibly with two-factor authentication (e.g. fingerprint / token).

Alternatively or additionally, certificates can be used to establish identity.

After authentication comes authorisation. Role and rights management decides whether the user is actually authorised to access the requested resource (trust journey).


What are the principles of Zero Trust architecture?

  • No implicit trust
    Every entity is considered insecure. No automatic trust is granted based on location or network position.
  • Micro-segmentation
    The network is divided into small, isolated segments. Each of these segments is subject to strict access controls so that access to resources is minimised.
  • Identity and authorisation management
    Strong authentication and authorisation are crucial. Users must prove their identity and access to resources is granted based on the necessary authorisations.
  • Monitoring and analysis
    Network traffic, user activity and other relevant events are constantly monitored. This enables early detection of anomalies or suspicious behaviour.
  • Minimisation of rights
    Users and systems are only granted the minimum rights required to fulfil their tasks. This reduces the risk of misuse or unauthorised access in the event of a compromise.
  • Secure applications
    The security of applications is guaranteed by certain principles. These include secure development, regular security checks and the implementation of security controls.

Eine Frau mit Brille, die vor einem futuristischen grafischen Benutzerinterface sitztWhich companies rely on this architecture concept?

The principle is important for companies that handle processes online and therefore value a comprehensive security strategy. In other words, companies that

  • Manage sensitive data
    Financial, personal or health data must be protected at all times.
  • Have employees working remotely
    Employees must be able to access the corporate network from anywhere without jeopardising security. Mobile devices must be securely integrated into the network.
  • Use cloud-based services
    Services such as Amazon Web Services (AWS) must be securely integrated into the network architecture. Precise access control must be possible.



  • The Zero Trust architecture minimises the risk of attacks and data theft as every access is authenticated and encrypted.
  • Compliance is increased as all access is logged. This is important for compliance with legal and regulatory requirements.
  • Zero Trust offers greater flexibility. Conventional security concepts restrict access to certain networks or locations. Zero Trust, on the other hand, enables secure access from anywhere at any time. This is a prerequisite for remote working and cloud computing.
  • The implementation of a Zero Trust Framework can help to achieve security goals. These are defined, for example, in cybersecurity standards such as NIST or ISO 27001.


  • The Zero Trust approach can increase the complexity of the network architecture. Implementation requires detailed system analysis and careful monitoring of access. Configuring and managing everything properly can increase the workload.
  • Multi-factor authentication (MFA) and access restrictions affect the user experience. They make it difficult to integrate new applications and collaborate with third-party providers.
  • The implementation of Zero Trust requires additional investment in infrastructure and security software. More authentication processes are required. Systems are becoming increasingly complex. This may result in more work for IT teams.

Why is the Zero Trust model important in the IoT/OT environment?

The Internet of Things (IoT) and Operational Technology (OT) have specific security requirements and challenges. In these areas, many networked devices and systems are connected to each other in order to control and monitor operational processes. The following reasons need to be considered in particular:

  • Heterogeneous environments
    IoT and OT environments often include a variety of device types, operating systems and protocols. The Zero Trust approach takes this heterogeneity into account. It relies on individual authentication and authorisation for each device, regardless of its type.
  • Protection against device compromise
    Many IoT devices have limited resources. They therefore cannot always implement the same security measures as conventional IT devices. By applying Zero Trust, compromised devices do not automatically gain access to the entire network.
  • Dynamic environments
    IoT/OT environments are often dynamic and can change quickly. New devices can be added or removed. A zero-trust approach continuously checks the identity and authorisations of devices and users. This enables rapid adaptation.
  • Ensuring the integrity of data
    OT systems are often used to control physical processes. The integrity of data is crucial here. Zero Trust secures the entire communication path. This ensures that data from devices is authentic and unchanged.
  • Minimisation of attack vectors
    Zero Trust minimises attack potentials as access to resources is restricted to the minimum necessary. This reduces potential attack vector.
  • Security in OT networks
    Specialised network protocols and architectures are often used in OT environments. A zero-trust approach can ensure that these networks are secured just as carefully as conventional IT networks.
  • Compliance requirements
    Many industries are subject to strict compliance requirements. A zero trust approach can help fulfil these requirements by implementing a comprehensive security strategy.



bunte Lichtspur aus Nachtverkehr in der StadtDigital certificates and Zero Trust

Digital certificates are an important cryptographic tool for verifying the identity of users, devices and systems.

They use digital signatures to prove that they are who they claim to be. They also help to secure access to resources within the network.

They thus serve as an identity card for digital identities and for checking authorisations.

They also encrypt communication between all participants and prevent third parties from intercepting or manipulating the information.

In a zero-trust environment, a reliable authentication tool is therefore necessary. As a comprehensive certificate management tool, essendi xc issues digital certificates automatically. It follows defined compliance requirements and distributes them to the target systems (including IoT/OT devices).

It helps to implement the basic principles of Zero Trust strategy (authentication, secure communication, access control). This strengthens the security of the entire IT infrastructure. It is therefore an essential cornerstone for secure and smooth communication in zero trust environments.