WSO2 Enterprise Service Bus - Only 100% Open Source ESB

We have an upgraded version of WSO2 ESB - the cloud-enabled, 100% open source WSO2 Enterprise Integrator (WSO2 EI) that extends the ESB to include all the other key products and technologies from the WSO2 Integration Platform. It allows you to make enterprise data accessible by integrating cloud services and legacy software, and data stores, as well as transforming data seamlessly across different formats and transports with ESB and data services capabilities. WSO2 EI is 100% backward compatible with WSO2 ESB. Try it now!

WSO2 Enterprise Service Bus (WSO2 ESB) is a lightweight, high performance, comprehensive ESB. 100% open source, WSO2 ESB effectively addresses integration standards and supports all integration patterns, enabling interoperability among various heterogeneous systems and business applications.

Its intuitive visually supported tools offer users a smooth experience in development environments and production deployments. Designed for customization, WSO2 ESB incorporates ESB specific analytics dashboards to gain better insights into system performance. Equipped with drill-down capabilities, it allows users to instantly understand and trace mediation flows for better analysis.

With over a 150+ ready-made, easy to use connectors, freely available via the Connector Store, WSO2 ESB provides greater flexibility and agility to meet growing enterprise demands. The cloud-enabled, multi-tenant WSO2 ESB is also available on the public cloud as a service.


Deployed at the heart of an SOA architecture or on the edge, WSO2 ESB mediates, enriches and transforms messages across a variety of systems, including legacy applications, SaaS applications, as well as services and APIs.

Enables widespread integration use cases: as a service gateway, mediation engine across SAP, Salesforce, and as healthcare hub or in IoT scenarios, made possible by variety of transports such as Apache Kafka and MQTT.

Supports the entire set of enterprise integration patterns enabling interoperability among various heterogeneous systems and business applications.

Offers intuitive and visually supported development tools that provide a smooth experience in development environments and production deployments.

Publishes ESB specific analytics into visual dashboards for better decision making and with drill-down capabilities that enable detailed analyses.


WSO2 ESB is the core of the WSO2 integration platform, and can be associated with the WSO2 Data Services Server, which creates a clean data access layer on top of any source of data, and WSO2 Business Process Server which manages business processes across SOA, as well as WSO2’s Message Broker for guaranteed delivery scenarios and asynchronous, event-based, integration.


Connect Anything to Anything

  • Adapters to cloud services: 150+ connectors across various categories such as payments, CRM, ERP, social networks or legacy systems.
  • Transports: HTTP, HTTPS, WebSocket, POP, IMAP, SMTP, JMS 1.1, JMS 2.0, AMQP, RabbitMQ, FIX, TCP, UDP, FTPS, SFTP, MLLP and SMS, MQTT, Apache Kafka
  • Formats & protocols: JSON, XML, SOAP 1.1, SOAP 1.2, WS-*, HTML, EDI, HL7, OAGIS, Hessian, Text, JPEG, MP4, all binary formats and CORBA/IIOP
  • Adapters to COTS systems: SAP BAPI & IDoc, IBM WebSphere MQ, Oracle AQ and MSMQ

Route, Mediate and Transform

  • Routing: header based, content based, rule-based and priority-based routing
  • Mediation: support for all Enterprise Integration Patterns or EIPs (including scatter/gather, message filters, recipient list, dead-letter channels, guaranteed delivery and message enrichment), database integration, event publishing, logging & auditing, validation
  • Transformation: XSLT 1.0/2.0, XPath, XQuery and Smooks
  • Visual Data Mapping: Mapping input data into output data visually using Developer Studio

Acts as Message, Service, API, and Security Gateway

  • Expose existing applications & services over different protocols and message formats
    • Enable virtualization of services for loose coupling and SOA governance
    • Create service façades for legacy/non-standard services
    • Expose services & applications via RESTful APIs
  • Enforce and manage security centrally, including authentication, authorization, and entitlement
    • WS-Security, LDAP, Kerberos, OpenID, SAML, XACML
    • SSL tunneling and SSL profiles support for inbound and outbound scenarios
    • CRL/OCSP Certificate revocation verification
    • Policy enforcement and governance via WSO2 Governance Registry
  • Enable logging, audit and SLA monitoring, KPI monitoring
  • Ensure load balancing for scalability and failover for high availability of business endpoints

Get High Performance, High Availability, Scalability & Stability

  • Supports 1000s of concurrent non-blocking HTTP(S) connections per server
  • Pure streaming and on-demand processing of messages
  • Sub-millisecond latency for high-throughput scenarios
  • Supports highly available deployment
  • Enables horizontal scaling via clustering with stateless server architecture
  • Ensures long-term execution stability with low resource utilization

Ensure Lightweight, Developer-Friendly, and Easy Deployment

  • Tracing and debugging message mediation
  • Get declarative development with configuration instead of code
  • Enable easy configuration of fault tolerant mediations with support for error handling
  • Ensure server customization via feature provisioning of any WSO2 middleware capability
  • Extend configuration language with custom DSLs via templates
  • Embed scripting language code in Javascript, JRuby, Groovy, and more, as custom mediators
  • Develop and deploy via Integration with SVN, Maven, Ant, and other standard tools
  • Integrate with WSO2 Developer Studio, Eclipse-based IDE for all WSO2 products

Manage & Monitor

  • Ensure comprehensive management & monitoring Web console with enterprise-level security
  • Enable built-in collection and monitoring of standard access and performance statistics
  • Integrate with WSO2 Data Analytics Server for operational audit and KPI monitoring and management
  • Get flexible logging support with integration to enterprise logging systems
  • Ensure centralized configuration management across different environments with lifecycles and versioning via integration with WSO2 Governance Registry


  • Publish mediation statistics to the intuitive, visual dashboards
  • Create your own customized dashboards and visualize data
  • Monitor statistics for all artifacts types and system performance
  • Trace message mediation flows and identify bottlenecks