Summary
The documentation for client-to-node encryption does not specify that in order to enable client-to-node encryption, the jce libraries must be installed.
Symptoms
When they are not installed you will see the error Caused by: java.lang.IllegalArgumentException: Cannot support TLS_RSA_WITH_AES_256_CBC_SHA with currently installed providers in the cassandra system.log
Cause
The Oracle Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files 6 must be installed when enabling client-to-node encryption.