Protect user's information in the referral URL
<p>I decided to refresh my site today with a pair of upgrades. One of them is referring availability. So, as I method of referrer recognition, I am going to use special URL with referrer ID in it (if there is some other but better method, feel free to let me know about it). After I implemented the basics of that availability, I made a decision to make the system more secure. With that, I mean hiding the referrer's ID. Now, I am here, looking for suggestion on how can I make it secure (hidden or encrypted), but still be able to decrypt it on the server-side. Don't suggest me to use Base64 encryption, it's too simple and everyone can decrypt it these days.</p>

<p>I could try making my own system of encryption, what do you think?</p>
