In the rapidly developing industrial Internet of Things (e.g. with the Unified Namespace), selecting the right message protocol is crucial. MQTT and NATS are two prominent options, each with different features and use cases. This article looks at the main differences between the two protocols (MQTT vs NATS) and helps you to decide which protocol best suits your requirements.
Basics of NATS (Neural Autonomic Transport System)
NATS is an open, lightweight and powerful messaging system designed for the development of distributed applications. Originally developed by Derek Collison, NATS is now maintained by the Cloud Native Computing Foundation (CNCF) and is thus part of the vibrant ecosystem of cloud-native technologies. NATS is the up-and-coming enterprise service bus for the IIoT, which is used by start-ups (e.Go) and companies (Volvo, Schaeffler) alike. You can find more information here.
Basics of MQTT (Message Queuing Telemetry Transport)
MQTT (Message Queuing Telemetry Transport) is a lightweight messaging protocol that was originally developed for networks with low bandwidth and high latency. This is particularly relevant in IoT scenarios (e.g. integration of external sensors). Developed by IBM, MQTT is based on a publish/subscribe model. This makes the standard very scalable and efficient in the distribution of information to a large number of subscribers.
You can find more information here.
MQTT vs NATS: Welches Protokoll eignet sich für den Unified Namespace?
The Unified Namespace (UNS) is a data-centric architecture that significantly facilitates data exchange between OT devices and IT applications. A unified namespace (UNS) is a non-hierarchical system architecture in which all data is uniformly accessible (data structure and naming convention) in a central broker. This makes it easier to access and share data across systems and locations. This makes it easier to access and share data across systems and locations. The following paragraphs describe the advantages of both systems and thus support broker selection. 
MQTT vs NATS – what are the similarities?
Messaging pattern
- MQTT: MQTT primarily uses a publish-subscribe model in which messages are published in topics and subscribers receive these messages. This model is very effective for IoT scenarios in which devices need to communicate with a central broker.
- NATS: NATS supports multiple messaging patterns, including publish-subscribe, request-reply and point-to-point messaging. This versatility makes NATS suitable for a wider range of applications, from simple message distribution to complex service orchestrations.
Security
- MQTT: Security in MQTT is simple, with built-in support for TLS (Transport Layer Security) and username/password authentication. These functions ensure secure communication between devices and the broker.
- NATS: NATS requires additional configuration for TLS, but supports token-based authentication and can be integrated with external authentication providers. This flexibility enables NATS to fulfill various security requirements in different application scenarios.
MQTT vs NATS – what are the differences?
Design and use cases
- MQTT: MQTT is primarily designed for IoT applications (Internet of Things). It is ideal for environments in which low bandwidths and high latency times are common. Its lightweight design makes it ideal for connecting remote sensors, smart home devices and other resource-constrained hardware.
- NATS: NATS, on the other hand, was developed for modern, data-intensive applications that require high performance and scalability. It serves as a universal messaging system that is suitable for cloud-native applications, microservices architectures and real-time data streaming.
Protocol complexity
- MQTT: Despite its simplicity, MQTT offers robust features such as Quality of Service (QoS) levels and stored messages. These functions ensure the reliable delivery and maintenance of messages, which is crucial in IoT scenarios. MQTT supports three QoS levels: at most once, at least once and exactly once. These levels provide flexibility in messaging guarantees, allowing developers to balance performance and reliability depending on the application requirements.
- NATS: NATS was developed to be even simpler and leaner than MQTT and focuses exclusively on the core functions of message transmission. This minimalist approach reduces overhead and improves performance, making NATS a preferred choice for applications where speed and efficiency are paramount. On the downside, NATS offers a “one-time at most” delivery by default. However, NATS Streaming enhances this with additional reliability features that ensure more robust message delivery for critical applications.
Performance and scalability
- MQTT: Although MQTT is also scalable, it is particularly suitable for networks with limited bandwidth and resource-limited devices. Its design ensures reliable communication even under difficult network conditions, which is often the case in IoT applications. The scaling of MQTT therefore requires additional configuration and setup for clustering. Brokers such as EMQX or HiveMQ, which offer the necessary clustering functions, are often used to implement scalable MQTT deployments.
- NATS: NATS is well-known for its speed and scalability, making it especially suitable for environments with high throughput. Its architecture supports high-speed messaging and can easily handle a large number of simultaneous connections. Basically it makes the system ideal for real-time analytics and big data applications. In addition, native support for clustering and automatic node detection simplifies scaling.
Conclusion
Both MQTT and NATS have their unique strengths, and the choice between them depends on your specific use case. MQTT is well suited for IoT applications with limited resources and network conditions, while NATS offers superior performance and scalability for data-intensive, modern applications. However, the requirements of your application should be checked and a specific selection made for the concrete selection of the protocol.
