Encrypting connection between httpd and TC;

The only way to encrypt the data between Apache httpd and Tomcat is to use mod_proxy with https.

In httpd.conf you need something like:

SSLProxyEngine On
SSLProxyVerify require
SSLProxyCACertificateFile conf/cacert.pem
SSLProxyMachineCertificateFile conf/proxy.pem
ProxyPass / https://127.0.0.1:8443/
ProxyPassReverse / https://127.0.0.1:8443/

note: conf/proxy.pem should contain both key and certificate (and the certificate must be trusted by Tomcat).

note: conf/cacert.pem must contain the CA that signed the Tomcat certificate.