What Is a Non-Human Identity (NHI)?

Updated on October 24, 2025

A Non-Human Identity (NHI) is a digital identity that represents an entity other than a human user. This broad category includes identities for applications, services, devices, and other automated processes that need to authenticate and access resources in a network. As organizations adopt cloud computing, IoT (Internet of Things) devices, and microservices architectures, the number of NHIs is growing exponentially. Managing and securing these identities is a critical challenge, as they often have privileged access to sensitive data and systems.

Definition and Core Concepts

A Non-Human Identity is any identity used to prove the authenticity of a system, application, or process. Unlike human identities, which are often tied to a user’s credentials and attributes, an NHI is typically based on a certificate, a cryptographic key, a token, or an API key. The primary purpose of an NHI is to enable secure, programmatic access between different systems without human intervention.

Foundational concepts:

• Machine-to-Machine (M2M) Communication: Communication between two or more devices or services without human interaction. NHIs are essential for securing M2M communication.
• Privileged Access: NHIs often have privileged access to systems and data. For example, a service account might have the ability to read and write to a database.
• Service Account: A traditional type of NHI that is typically a regular user account used by a service or application.
• API Key: A key used to authenticate an application to an API. This is a common form of NHI.

How It Works

The lifecycle of a Non-Human Identity is different from that of a human identity.

• Creation: An NHI is provisioned by an administrator or an automated process. The identity is often created with a unique identifier and a credential, such as a cryptographic key pair.
• Authentication: When an application or service needs to access a resource, it presents its NHI to a target system. The target system validates the identity using its credentials. For example, a web server might use a certificate to prove its identity to a database server.
• Authorization: Once the NHI is authenticated, the target system uses its attributes—its role, its permissions—to determine what it is authorized to do.
• Rotation: To enhance security, an NHI’s credentials should be rotated periodically, often on an automated basis. This is a key difference from human identities, where password rotation is often a manual process.

Key Features and Components

• Programmatic: NHIs are designed for automated use by applications and services. They do not have a user interface or a login screen.
• Privileged: NHIs often have a high level of privilege, which makes them a prime target for attackers.
• Dynamic: The number of NHIs in an organization is constantly changing, making them difficult to manage and monitor.
• Identity and Access Management (IAM): Managing NHIs requires a robust IAM framework that can handle the scale and complexity of these identities.

Use Cases and Applications

NHIs are a foundational component of modern IT infrastructure.

• Microservices Architecture: In a microservices environment, each service uses an NHI to authenticate to other services. This allows for secure, decentralized communication across the architecture.
• Internet of Things (IoT): IoT devices, such as smart cameras and industrial sensors, use NHIs to authenticate to a central management platform. This ensures that only authorized devices can transmit data.
• Cloud Computing: Cloud services use NHIs to authenticate to other cloud services and to on-premises systems. This enables hybrid and multi-cloud deployments.
• Automation and Scripting: Scripts and automation tools use NHIs to authenticate to servers and databases to perform administrative tasks. This reduces manual intervention and improves operational efficiency.

Advantages and Trade-Offs

• Advantages: NHIs enable secure, automated communication between systems. They are essential for modern, scalable architectures. Without NHIs, organizations would struggle to implement cloud computing, IoT, and microservices at scale.
• Trade-offs: NHIs can be difficult to manage and monitor due to their sheer number and privileged nature. If an NHI is compromised, it can be used by an attacker to gain a foothold in the network. The dynamic nature of NHIs means that traditional identity management approaches often fall short.

Key Terms Appendix

• Identity and Access Management (IAM): The framework of policies and technologies used to manage digital identities and control access to resources.
• Service Account: A traditional type of non-human identity.
• API Key: A key used to authenticate an application to an API.
• Microservices: A software architecture where an application is composed of a number of small, independent services.
• Internet of Things (IoT): A network of physical devices that are embedded with sensors and software to connect and exchange data.
• Machine-to-Machine (M2M) Communication: Direct communication between devices or applications without human intervention.
• Credential Rotation: The process of periodically changing authentication credentials to reduce security risk.