I pass a loan ID, social security number and zipcode in url.

```
LoanID: 205689
ssn No: 555-896-4569
Zip code: 12345

```

the url is `http://localhost/Product/abc/manager/internet/PayCredential.aspx?LoanID=205689`

I need to convert the social security number and zip code into a hashcode for security purposes and pass them in this url. I would then decrypt them when the page is called. How can I do this?