PassThrough Transport is a non-blocking HTTP transport implementation based on HTTP Core NIO, and is the default HTTP transport shipped with WSO2 ESBthe ESB Profile of WSO2 Enterprise Integrator (WSO2 EI). Although the PassThrough Transport is somewhat similar to the NHTTP transport, it overcomes all the limitations of the NHTTP transport and provides a significant performance gain. The PassThrough Transport also has a simpler and cleaner model for forwarding messages back and forth.
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Setting the CertificateRevocationVerifier parameter at the transport listener allows you to verify client certificates when a client tries to make an HTTPS connection with the ESB Profile of WSO2 EI. Following is a sample transport listener configuration that you can add in the axis2.xml file to enable certificate revocation verification:
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Setting the CertificateRevocationVerifier parameter at the transport sender allows you to verify server certificates when the ESB Profile of WSO2 EI tries to make an HTTPS connection with a backend server. Following is a sample transport sender configuration that you can add in the axis2.xml file to enable certificate revocation verification:
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When the CertificateRevocationVerifier parameter is set to true, the ESB Profile of WSO2 EI attempts to use the Online Certificate Status Protocol (OCSP) to verify with the certificate authority at the handshake phase of the SSL protocol. If the OCSP is not supported by the certificate authority, the ESB Profile of WSO2 EI uses Certified Revocation Lists (CRL) instead. The verification process checks all the certificates in a certificate chain.
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