Text read ActiveMQ vs RabbitMQ over an Image of a rabbit on a rocket

ActiveMQ vs RabbitMQ Message Broker: Understanding the Differences

Both these tools are used in production environments to manage message exchange between distributed systems.

Before we start comparing the differences between the two products, let us first find out how they’re similar.

Let’s get the obvious one out of the way first. They both enable data exchange between interconnected applications without directly integrating them. They receive, queue, and route messages between producers (or senders) and consumers (or receivers).

Both tools are available for free and have a large community that’s actively working on improving the products’ features and performance. With developers collaborating and driving continuous improvements and innovations, RabbitMQ and ActiveMQ are highly optimised for performance. They can handle large message throughput and process high volumes of data quickly and consistently.

RabbitMQ and ActiveMQ can both scale up without much loss in performance. If you want to increase their workloads, simply add more instances or clustering servers. You’ll continue to get dependable performance even under high pressure.

The two message brokers support a variety of protocols. However, since we’re discussing similarities, let’s look at the ones they both support, which are:

  • AMQP (Advanced Message Queuing Protocol)
  • MQTT (Message Queuing Telemetry Transport)
  • STOMP (Simple Text Oriented Messaging Protocol)

This makes them both quite flexible and suitable for all sorts of purposes. Speaking of which…

Both message brokers are versatile and work well across different industries because they share information quickly and efficiently between systems. This makes them ideal for any sector where communication and real-time updates are important, like finance, telecommunications, and e-commerce.

Whilst there are some key similarities between the two message brokers, we wouldn’t be trying to determine which of them was better for you if there weren’t any significant differences. Let’s see what they are.

Any digital solution you build must be able to scale up quickly and effectively. What makes these two solutions so popular is that they can be configured to deal with growing workloads quite easily. Where they differ is how they do it. 

ActiveMQ is designed to meet all requirements of an application with a single broker. If, however, the messaging scenarios become more complicated, a network of brokers can be used to make a cluster of multiple interconnected servers.

On the other hand, RabbitMQ has clustering built into it, which provides seamless failover and horizontal scaling. This clustering is what allows it to continue to function even if one of the nodes fails, as the others then take over, so producers and consumers have an uninterrupted flow of information. You can also scale horizontally by adding more clusters to handle a growing workload.

ActiveMQ supports horizontal, vertical, and traffic partitioning using broker networks, allowing for message routing across multiple brokers. RabbitMQ, on the other hand, supports vertical and horizontal scaling but not traffic partitioning—at least, not natively. However, it can achieve similar functionality using consistent-hashing exchanges, federated queues, or shovels.

This means you get more flexibility in deployment for ActiveMQ.

RabbitMQ, meanwhile, is much simpler to launch but less customisable for complex use cases. However, it shines in a cloud-native environment, where horizontal scaling is all you need.

RabbitMQ was built around the AMQP standard by LShift and CohesiveFT before being acquired by Rabbit Technologies Ltd. It’s licensed under the Mozilla Public License 2.0 (MPL 2.0). This allows users to make modifications to the product. However, those changes to the code must be shared publicly if those modifications are redistributed as part of the same software.

ActiveMQ is based on the Java Message Service (JMS) and works very well with applications that rely on Java. Since it was created by Apache Software Foundation and distributed under the Apache license, it doesn’t require public sharing if you make modifications to its code, even if you do redistribute it. The fact that it allows proprietary changes makes it great for commercial products.

One of the benefits of being built around the AMQP standards is that RabbitMQ is compatible with a range of platforms and languages. In addition to native Erlang support, the language in which it was written, the message broker also supports Elixir (which runs on Erlang), Java, Python, Ruby, PHP, C# (and the .NET runtime), C/C++, JavaScript, Go, Swift, Perl, and Scala. Whilst it does support Swift and Haskell, it’s only through third-party libraries.

ActiveMQ is written in Java, which it natively supports along with the JMP API. The other languages it supports are C/C++, C#, Python, Ruby, Perl, PHP, JavaScript, Groovy, and Scala.

Both ActiveMQ and RabbitMQ support AMQP 0.9.1 and 1.0, MQTT, and STOMP. (RabbitMQ defaults to AMQP 0.9.1, while ActiveMQ natively supports AMQP 1.0.)

In addition, ActiveMQ supports JMS (Java Message Service), OpenWire (ActiveMQ’s native protocol), REST API, XMPP, WSIF, WS-Notification, UDP/TCP Multicast, although some of these are rarely used in production.

Meanwhile, RabbitMQ supports  HTTP/HTTPS (for management API and WebSockets), WebSockets (for AMQP/STOMP transport), and Custom protocols via plugins.

In synchronous mode, the sender waits for confirmation that the message has been received before proceeding. It is, therefore, more reliable and more suitable for use cases where message acknowledgement is necessary, such as financial transactions. The asynchronous mode, which doesn’t need confirmation to continue processes, is faster and better for real-time systems.

RabbitMQ can operate both synchronously and asynchronously, which makes it more versatile. ActiveMQ, on the other, is natively synchronous. However, its configuration can be modified to change it to asynchronous mode.

ActiveMQ can operate on both a push and a pull model. It can check for new messages frequently as well as send them to the next part of the system automatically. On the other hand, RabbitMQ operates primarily on the push-based model (basic.consume), where messages are automatically delivered to consumers. 

However, it also supports synchronous polling with basic.get, which functions as a pull model but isn’t efficient for high-throughput applications due to increased round trip latency. 

A more practical approach to simulating pull behaviour is using basic.consume with a low prefetch count (e.g., basic.qos(prefetch=1)) to ensure that a consumer receives only one unacknowledged message at a time before requesting the next one.

RabbitMQ uses mirrored queues, which copy the queue data over multiple nodes. If one fails, others can take over to ensure high availability. However, this method focuses more on redundancy and real-time failover than long-term persistence. It can also become resource-intensive in larger clusters.

Since the data is only replicated across a subset of nodes instead of the entire queue mirrored on all nodes, quorum queues are a better choice for large-scale distributed systems or where data integrity is important.

In contrast, ActiveMQ uses a master-slave replication model, where messages are stored on the disk by the master node. They are also replicated onto slave nodes for failover. As a result, persistent messages are retained even in case of failures.

Both RabbitMQ and ActiveMQ take security seriously, offering SSL/TLS encryption and username/password authentication.

RabbitMQ supports LDAP, client certificates, SSL/TLS, and granular Access Control Lists (ACLs) at the virtual host level. OAuth 2.0 is supported through external plugins or custom authentication methods. It excels in simplicity and extensibility with plugins. 

Meanwhile, ActiveMQ provides advanced options like JAAS-based authentication, LDAP integration, and a pluggable security framework for custom solutions. It is perfectly suited for enterprise environments with its broker-to-broker encryption and detailed authorisation controls for queues and topics. 

Both systems secure their management interfaces with HTTPS and password-based access, ensuring administrative security.

Thomas Bhatia - RabbitMQ Consultant, Seventh State

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