Microservices architecture has long been a key approach in which a product is broken down into independent services instead of being a single monolith. Each service is responsible for its own business function and can be developed, updated, and deployed separately. This gives users the ability to independently deploy services in different environments, scale components to meet load demands, and reduce risks during updates, while the failure of a single service no longer brings down the entire system. This model also makes it more convenient for the vendor to evolve the product and sell extensions.
However, technical complexities also arise. Customer deployment is more complex, requiring a prepared infrastructure with container orchestration, dependency management, and good network connectivity between services.
Security requirements also increase. Instead of a single boundary (like an external API or UI), a microservices architecture has many: the API of each service, inter-service communication, environment variables, secrets, and network permissions. And finally, the act of software licensing itself becomes more complicated. The developer must determine which service checks the license, where it is stored, how to count instances, how to act during scaling and container migration, and how to ensure fault tolerance.
Why Microservices Complicate Licensing
With monolithic software, the issue is typically resolved quite simply: the application runs on a specific machine, accesses a local or network key, and retrieves information on the current license terms, such as the right to operate, validity periods, or feature limitations.
In a microservices architecture, however, everything is significantly more complex for several reasons.
- The number of services can reach the hundreds;
- each service can have multiple concurrent instances that start and stop based on load;
- and containers can migrate between orchestrator nodes.
- Customer infrastructure is typically heterogeneous—with services in containers, VMs, and on physical servers;
- the client's internal network may be isolated from the internet, limiting external license checks;
- and interaction between microservices occurs over the network.
- The physical characteristics of a specific machine (hardware identifiers, MAC addresses, etc.) cease to be a reliable basis for license binding.
Virtualization and containers undermine the reliability of traditional license binding to hardware identifiers. Inside a virtual environment, an application sees virtual runtime characteristics, not physical hardware. Furthermore, the environment can change as containers migrate between nodes. This dynamic reality complicates traditional node-locking—the practice of binding a license to a specific node or device—and demands a far more sophisticated licensing model.
As a result, the vendor faces a number of questions:
- Where should the license file (or key) be located, and what component is responsible for checking the right to run—each microservice individually or a dedicated licensing service?
- How to limit the number of concurrently running instances and how to license different types of microservices?
- How do you ensure business continuity during a brief network failure, so that a temporary loss of connection to the license server doesn’t halt critical services? And how do you protect against the unauthorized copying and distribution of entire containers?
- How to measure usage by time, number of API calls, or volume of data processed?
- How to design a licensing system that avoids becoming so cumbersome that it interferes with the product's normal operation?
Recommendations for Solving Common Microservice Licensing Challenges
Let's explore how to reliably protect and license software that is built on a microservice architecture and runs in a distributed environment.
Decentralized Execution
A microservice system has no single point of execution; one customer might run three instances, another 30. If the license doesn't control the instance count, a customer can use more resources than purchased.
Solution: Use network licenses to control concurrent usage. Each instance requests a license from a license manager at startup. If the limit is reached, the service won't start or will run in a limited mode. When an instance stops, the license is released back into the pool for another instance to use.
Container Migration Between Nodes
In Kubernetes or other orchestration systems, a container can be recreated on a different node. A license that is hard-bound to a specific node makes normal operations impossible.
Solution: Avoid binding licenses to specific containers or worker nodes. Instead, host the network license and license manager on a dedicated node, and have microservices request authorization over the network.
Isolated Corporate Networks
Many B2B customers operate in isolated, or air-gapped, networks. They may lack persistent internet access, or have no internet connectivity whatsoever.
Solution: Support both online and offline license activation and updates. License validation must be performed autonomously, without reliance on external services.
Licensing Fault Tolerance
If a microservice cannot contact the license manager due to a brief network outage, the product must not immediately shut down. This is a critical requirement for any large customer.
Solution: Implement a controlled grace period or temporary license caching. A service can locally store its authorization for a limited time to continue operating during brief network issues. The cache's duration and terms must be limited to prevent it from being used to bypass licensing.
Protection Against Copying and Reverse-Engineering
Licensing alone does not protect your actual code. If a valuable algorithm sits unprotected inside a container, it can be studied, copied, patched, or modified to disable the license check.
Solution: protect only the most valuable parts of the product, like algorithms, calculation engines, unique business rules, and cryptographically sensitive code. It is highly recommended to protect these code sections using automated anti-reverse-engineering tools, which significantly complicate an attacker's ability to compromise the software.
Commercial Tracking Complexity
While microservices enable flexible product sales, the lack of centralized tracking can quickly lead to chaos. Customers may have different module sets, instance counts per microservice, terms, trials, updates, and license transfers.
Solution: Use a license lifecycle management system to handle license creation, issuance, renewal, suspension, and transfer, as well as to track customers, products, and modules. The system should allow sales managers to configure licenses with required restrictions and generate updates for licenses already deployed to the end user.
Performance and Scalability
The number of microservices and their corresponding instances can easily reach into the hundreds. Microservices may restart regularly and contact the network license to get authorization to run and operate based on existing licensing constraints.
Solution: Use a license manager designed from the ground up for high performance and stability, with the ability to cache licensing constraints on end-user devices to reduce network load.
License Security
A network license, whether installed on a host or within a dedicated container, must be reliably protected against unauthorized duplication and any modification of its licensing constraints.
Solution: Use secure, encrypted storage for licensing constraints in a software or hardware key. When using a software key, it is crucial to implement a system of flexible and reliable bindings to the parameters of the operating environment. In cases of heightened security requirements, the network license must be stored in a hardware key.
Ease of Administration
The end-user's system administrator must be able to quickly diagnose any situation that arises from problems in the software's operation.
Solution: The network license manager must not only issue licenses on request but also display current license usage statistics, allow for configuring microservice access policies, and log all relevant events. For example, it should log when a user reaches the limits set by the license. This allows the customer and sales managers to get statistics for making an informed decision about expanding the existing license pool.
Platform for Microservice Protection and Licensing
A microservice architecture makes B2B software inherently more flexible, scalable, and easier to evolve over time. But the product architecture and required infrastructure become significantly more complex and require additional expertise in building and administering microservice architectures. In addition, the nature of licensing changes, and instead of one application on one server, a distributed system of many services, containers, and instances appears.
To prevent such an architecture from destroying the commercial model, licensing must be designed in the early stages of development. It is critical to determine in advance which microservices have commercial value, which limits to control, where the license will be located, how the product will work in closed networks, and what will happen during a temporary network failure.
Instead of mechanically forcing a legacy monolithic licensing model onto a new architecture, the optimal strategy is to build a flexible system featuring network licenses, a license manager for network-based distribution, modular permissions, instance and thread limits, a controlled offline/grace period, statistics collection, and protection for critical code and data.
This approach turns microservices into a tool for precise product packaging, flexible pricing, and a clear licensing scheme.
Guardant is a prime example of a solution that supports these mechanisms, serving as a professional platform for the protection, licensing, and sales management of software products. It provides a complete ecosystem of tools for monetizing everything from classic, monolithic software to modern microservice-based architectures.
Licenses are written to Guardant software keys or hardware (USB) keys, which serve as secure containers for the licensing terms. These keys define the list of permitted microservices and the number of their instances, along with additional restrictions such as runtime, user counts, number of launches, compute threads, and available modules. Software keys are bound to specific environment parameters, a process that prevents the unauthorized duplication or modification of license rights.
The Guardant Control Center network manager handles the distribution of licenses to containers across the network, is built for high-load environments, and allows administrators to configure access, collect statistics, and cache data on end-user devices.
When an application starts, it checks for the presence of a valid license and its restrictions by communicating with the Guardant Licensing API. An additional layer of security is implemented using the Guardant Protection Studio utility, which protects native, .NET, and even Python-based software from reverse engineering. The Guardant Station management service empowers the vendor to handle the entire license lifecycle, including generating licenses with specific restrictions, as well as managing their updates, delivery, and tracking. It serves as the central component of the entire software monetization platform. The system makes it possible to implement new software licensing schemes without involving the development department or modifying source code.
The system is a flexible SDK with the necessary components to easily and effectively monetize software products, letting developers focus on core functionality that end-users pay for.
Conclusions
Microservice architecture is an established B2B development practice, and its use will grow. System complexity requires rethinking monetization. Companies must design licensing systems for distributed operations from the start, using specialized platforms for licensing, protection, and product management.