Solace PubSub+ Event Broker vs ZeroMQ
Solace PubSub+ Event Broker
solace.comZeroMQ
zeromq.orgSide by side
| Figure | Solace PubSub+ Event Broker | ZeroMQ |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | — |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | Yes |
| Plans published | 5 | 1 |
| Spec score · Message Broker Software | 8.2 (#13) | 7.4 (#31) |
| Spec score · Message Queue (MQ) Software | 8.2 (#11) | 7.4 (#22) |
| Intended users | The product page describes the broker for enterprises with demanding messaging and streaming needs and for connecting applications, customers, partners, and devices. | The site describes ZeroMQ as aimed at developers building distributed or concurrent applications. |
| Messaging patterns | The product supports publish/subscribe, queuing, request/reply, streaming and replay use cases. | It supports patterns including publish-subscribe, request-reply, and client-server. |
| Security | Solace Cloud states that its infrastructure for customer event broker services, Solace Home Cloud, and the Cloud Console complies with GDPR, SOC 2 Type 2, and ISO 27001. | The listed libzmq and many language bindings support PLAIN and CURVE mechanisms. |
Plans
Solace PubSub+ Event Broker
- Event Broker Software StandardFree
- Solace Cloud Event Broker TrialFree
- Solace Cloud trialFree
- Solace Event Broker Software Free VersionFree
- Event Broker Software EnterprisePriced on request
In their own words
Solace PubSub+ Event Broker
Solace PubSub+ Event Broker streams information among applications, AI agents, and devices across cloud, on-premises, and edge environments. Multiple brokers can form an event mesh to route data across clouds, data centers, and geographies. It is offered as a cloud service, software, or appliance, for deployment in clouds, data centers, and remote locations. Messaging features include exchange patterns, qualities of service, caching, partitioned queues, and replay. Supported protocols include AMQP, Kafka, MQTT, REST, and WebSocket, alongside APIs for programming languages. Solace offers supported micro-integrations for applications, cloud services, and integration tools. Monitoring includes custom dashboards and alerts, and distributed tracing is broker-native and based on OpenTelemetry. Cloud services enable secure protocol ports by default and disable plain-text ports by default. Free options include a 30-day cloud trial and a free enterprise-grade software version. Solace was founded in 2001 and is headquartered in Ottawa, Ontario, Canada.
ZeroMQ
ZeroMQ is a free, open-source asynchronous messaging library for developers building distributed or concurrent applications. A system using it can run without a dedicated broker, with patterns such as publish-subscribe, request-reply and client-server. It carries messages over transports including TCP, in-process and inter-process communication, multicast and WebSocket. The project lists language bindings and libraries for C, C++, C#, Dart, Erlang, F#, Go, Haskell, Java, Node.js, Perl, Python, Ruby, Rust and Zig. Supported protocols also include ZMTP, UDP, IPC, PGM, NORM and TIPC, and delivery guarantees are configurable. The project says libzmq and many bindings support PLAIN and CURVE security mechanisms. libzmq is licensed under MPL-2.0; the project says closed-source commercial applications do not need a separate commercial license. Installation guidance covers macOS, Linux distributions and Windows. One documented constraint affects Go’s zmq4 wrapper: it requires ZeroMQ and development files to be installed and cannot be cross-compiled. ZeroMQ is self-hosted and listed at free.