Client-cert authentication requires that each client connecting to the server have a certificate to authenticate. This is generally regarded as stronger authentication than a password as it requires the client to have the certificate and not just know a password. Rationale: Certificate based authentication is more secure than password based authentication.
Solution
In the Connector element, set the clientAuth parameter to true and the certificateVerification to required <-- Define a SSL Coyote HTTP/1.1 Connector on port 8443 --> <Connector port='8443' minProcessors='5' maxProcessors='75' enableLookups='true' disableUploadTimeout='true' acceptCount='100' debug='0' scheme='https' secure='true'; clientAuth='true' sslProtocol='TLS'/> ... <Connector ...> <SSLHostConfig certificateVerification='required' /> Default Value: Not configured