Directly From URL

I have the page "content.asp" and it is called from the "menu.asp" page.
Two page are on diffenent servers and on different Databases.
Users who request the content.asp page are authenticated when they enter the
"menu.asp" page.
So, if another authentication is required when users enter "conent.asp", it
is redundent, I think.
Finally, I want to reject users requests for content.asp if the page
"contnet.asp" is requested directly from URL.
Are there ways if the page content.asp is called from URL or the <a> tag in
the menu.asp?