Does anyone know about single sign on thing

i am working on website where the client have half of portion like redemption points with the other company and i have to use those points

I have three links on my site like account info , points balance which are with other company.

The other company told me that i have to use single sign on to make the members redirect ot those pages without signing again .


they gave me one encrypted key to use

But i have no idea how to use that . Can anyone help??

What programming language are you using?

I am using php

Am not good at all at PHP but I can advise you to read the following articles in the right order:


http://en.wikipedia.org/wiki/Single_sign-on
http://www.opengroup.org/security/sso/
http://wiki.developerforce.com/index.php/How_to_Implement_Single_Sign-On_with_Force.com


This will clarify what is SSO in general and how to implement it using PHP.