Encode and decode password

In my LOGIN and LOGOUT module I am calling a cfc method using javascript ajax. But I want to pass password after encoding.

Is there any way to encode the password to be send to CFC method so that I should be able to decode the same also in the CFC method.

My javascript code is like below.

xmlhttp.open("POST","cfc/useraccess.cfc?method=checkUserAccess&usernam e="+username+"&password="+password,true);

xmlhttp.send();

I want to pass this password in encoded form.

Any one have any idea on this.

Your help is well appreciated.