Solace PubSub+vs
Apache Kafka
Apache Kafka: If your workload is durable log streaming and reprocessing rather than multi-protocol routing
Solace PubSub+
Multi-protocol event broker sold as software, cloud service or a hardware appliance
As of 31 August 2026, Solace PubSub+ is free to use. An enterprise event broker that speaks MQTT, AMQP, JMS, REST and its own protocol on one bus, and is one of very few vendors still selling a purpose-built messaging hardware appliance. Softwr lists it under Databases. Solace PubSub+ is made by Solace Corporation, available on Linux, Docker, Kubernetes, Cloud.
Overview
What Solace PubSub+ does
Solace PubSub+ is an event broker platform covering publish-subscribe, queuing, request-reply and streaming across MQTT, AMQP 1.0, JMS, REST and the proprietary SMF protocol, so a Java service, an IoT device and a browser can exchange messages on the same topic hierarchy without adapters. Around the broker sits Event Portal, a catalogue and design tool for event schemas and their producers and consumers, and Mission Control for operations. Dynamic message routing lets geographically separated brokers form a mesh that forwards events based on subscription interest rather than static bridges. What distinguishes Solace commercially is deployment breadth in one product. The same broker runs as a managed cloud service, as software in your own Kubernetes or VMs, and as a purpose-built hardware appliance with messaging offloaded to an FPGA. Very few vendors still make messaging hardware, and for capital markets and exchange operators with hard latency budgets that appliance is the reason Solace is on the list at all. Buyers are banks, exchanges, airlines, retailers and industrial firms building an event mesh across regions and protocols. Nothing is published on price: everything runs through a sales process with broker tiers from ENT-250 to ENT-100K, fixed subscriptions or annual drawdown consumption licensing. A free Standard edition of the software broker exists with capacity limits and no support, which is enough to develop against but not to run a business on.
What people use it for
- A bank building an event mesh across regions where a Java JMS application and an MQTT mobile client must share the same topic space
- An exchange or trading platform with a latency budget that needs the hardware appliance rather than a software broker
- An airline distributing operational events to ground systems, aircraft and partner APIs over different protocols
- A manufacturer bridging factory MQTT telemetry into an enterprise Kafka estate without writing translation services
Related searches
The honest half
Where it falls short
Concrete and checkable, so you can decide whether any of them matter to you. This is the half of a review a vendor will not write about Solace PubSub+.
- No pricing is published at any tier, so evaluation requires a sales engagement before you can even judge whether it is in budget, and broker tier sizing determines cost in ways buyers frequently get wrong.
- The free Standard edition has hard capacity and support limits, which makes it useful for development but means any real deployment triggers a commercial negotiation.
- The proprietary SMF protocol gives the best performance and feature coverage, so teams that lean on it acquire real switching costs even though open protocols are supported.
- Operating a self-managed high availability broker pair with disaster recovery is a specialist task, and Solace expertise is scarce in the hiring market compared with Kafka skills.
- Event Portal and Mission Control are licensed as part of platform packages, so the governance tooling that makes an event mesh manageable is not simply included with the broker.
Cross-shopped
What people choose instead of Solace PubSub+
Each pairing was judged by two reviewers asking whether a buyer would genuinely weigh the two against each other. The ones that failed were deleted rather than published.
- Solace PubSub+vsRabbitMQ
RabbitMQ: If you need conventional enterprise queuing at a fraction of the cost and can accept fewer protocols
- Solace PubSub+vsApache Pulsar
Apache Pulsar: If you want multi-tenant streaming with geo-replication under an open source licence
Pricing
What Solace PubSub+ costs
Taken from the vendor's own pricing page. Prices move, so check before you buy.
Software Event Broker Standard
Free
- Free for production within capacity limits
- Single node, capped connections and queues
- No vendor support
- Same protocol coverage as paid editions
Solace Cloud
On request
- Managed brokers in tiers from ENT-250 to ENT-100K
- Foundation, Accelerate and Scale platform packages
- Fixed subscription or annual consumption drawdown
- No prices published, quoted by sales
Software Enterprise self-managed
On request
- Deploy in your own Kubernetes, VMs or data centre
- High availability and disaster recovery
- Support with SLA
- Quoted by broker tier and capacity
Hardware appliance
On request
- Purpose-built appliance with FPGA message offload
- Deterministic low latency
- Sold with support contract
- Quoted per unit
Capabilities
Features
Multi-protocol broker
MQTT, AMQP 1.0, JMS, REST and SMF on a single topic space
Dynamic message routing
Interest-based event forwarding between brokers across regions
Hardware appliance
FPGA-accelerated appliance option for latency-sensitive deployments
Event Portal
Catalogue of event schemas, applications and their relationships
Guaranteed delivery
Persistent queues with acknowledgement and replay from a message spool
Mission Control
Monitoring, provisioning and lifecycle management across deployments
Topic hierarchies and wildcards
Fine-grained subscription filtering without consumer-side discard
Kafka and MQ bridging
Connectors to Kafka, IBM MQ and integration platforms
Answered, with sources
Questions people ask
Each answer names the page it came from, so you can check it rather than take our word for it.
Is there a free version of Solace?
Yes, the Standard edition of the software event broker is free for production within capacity limits, with no vendor support.
Does Solace publish prices?
No. Cloud, software and appliance are all quoted, based on broker tier from ENT-250 to ENT-100K and licensing model.
Why buy an appliance in 2026?
Deterministic low latency with message processing offloaded to hardware, which matters in capital markets and little elsewhere.
Can it replace Kafka?
Not for log retention and stream reprocessing. It is stronger at multi-protocol routing and guaranteed delivery, and the two are often bridged.
Keep looking
Where to go from Solace PubSub+
- Solace PubSub+ alternativesEvery product people weigh against it
- Solace PubSub+ pricingPlans, floors and what the tiers exclude
- Solace PubSub+ badgesWhich rules it meets, and the figure behind each
- All Databases softwareThe full category
- Best Databases softwareThe shortlist, and how it was cut
Best Databases software for
Compare Solace PubSub+ with
- RabbitMQ
- Apache Pulsar
- TIBCO Enterprise Message Service
- NATS
- EMQX
- VerneMQ
- Couchbase
- Oracle Database
- Microsoft SQL Server
- IBM Db2
- DuckDB
- DynamoDB
- Apache Kafka
- NATS
- Couchbase
- Azure SQL
- Apache Solr
- Apache Flink
Other Databases software
Cloud-native messaging and streaming with separated storage
Open source10 researched notesJMS message broker underpinning bank and telecom estates, now maintained rather than expanded
Pricing on request12 researched notesErlang MQTT broker for large IoT fleets, relicensed to BSL with production free use limited to one node
Free, then $234/mo12 researched notesErlang MQTT broker whose source is Apache 2.0 but whose official binaries need a paid subscription
Free plan12 researched notesThe world's most complete, reliable, and secure database
Free, then $47,500/processor10 researched notesEnterprise-grade relational database management system
Free plan15 researched notesThe AI-powered database built for demanding enterprise workloads
Free, then $99/mo14 researched notesMIT-licensed analytical SQL database that runs inside your process, with no server, no dependencies and one writer at a time.
Free plan14 researched notesAWS-only managed key-value and document database with fixed per-partition throughput limits and no ad hoc queries.
Free, then $0.625/million writes14 researched notes
Softwr does not host reviews and shows no star rating for Solace PubSub+, because a rating we did not collect is not ours to publish. What is here is the pricing and platform detail from the vendor’s own pages, limitations we could state concretely, and alternatives a reviewer confirmed people weigh against it. Tell us if any of it is wrong.
More on Solace PubSub+
Solace PubSub+ alternatives
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Solace PubSub+ pricing
Every tier, and where the cost actually lands
Compare Solace PubSub+
Put it head to head with anything we hold
Solace PubSub+ badge
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