A transport is responsible for carrying messages that are in a specific format. WSO2 ESB supports all the widely used transports including HTTP/s, JMS, and VFS, and domain-specific transports like FIX. All WSO2 transports are directly or indirectly based on the Apache Axis2 transports framework. This framework provides two main interfaces that each transport implementation must implement.
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There are two main types of transports: blocking and non-blocking. In a blocking transport, the I/O threads get are blocked since because the same worker thread that sends the request to the server will remain remains open to receive the response, . These threads are blocked until messages are completely processed by the underlying Axis2 engine. However, in In non-blocking transports, the worker thread that sends the request will not wait for the response, and another thread will receive the response. TherebyTherefore, non-blocking transports increase the performance of the server.
For more information on transports, see the following topics:
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