OWA URL for Internal Users ONLY

Hi,

I've just installed 1 x Exchange 2010 SP2 server (EXC01) into a test domain (test.local). The only requirement for OWA is for Internal access, no external access. The default internal URL for OWA is https://exc01.test.local/owa but I don't want to expose this URL to users. Instead I would like users to access OWA through a URL such as https://mail.test.local/owa.  I would also like to follow this thread with ECP so the URL will be https://mail.test.local/ecp.

How can I achieve this?

Thanks in advance.

Andrew