To test a web server using SSL encryption (HTTPS), JMeter requires that an implementation of SSL be provided (such as Sun's Java Secure Sockets Extension -- JSSE ). Include the necessary encryption packages in JMeter's classpath . Also, update jmeter.properties by registering the SSL Provider.
There is also the SSL Manager , for greater control of certs.
Note: if you are running JDK1.4, then you do not have to download JSSE because Sun integrated it into JDK1.4 as a standard library.