title: Effect of encrypted data in campaign URLs on SEO
body: <p>I want to track incoming traffic to a website from campaigns. A campain link can be sent in an email or published on another website. When a campaign link is requested, the following values need to be tracked:</p>
  
  <ul>
  <li>unique reference ID of the mail in which the link was sent</li>
  <li>affiliate reference ID</li>
  <li>utm_source (Google Analytics)</li>
  <li>utm_campaign (Google Analytics)</li>
  <li>utm_medium (Google Analytics)</li>
  <li>... (maybe other values in the future)</li>
  </ul>
  
  <p>I could append these values in the querystring of the URL, but I don't like that approach because the website uses the hash part of the URL to identify the requested AJAX content. A querystring comes before the hash part and that way the URLs are ugly. Also, it's easier to process the campaign tracking on the server if all campaign URLs are processed by the same URL handler.</p>
  
  <p>My solution is to encrypt the values I want to track, plus the destination URL, with AES and encode that value with Base64. The resulting string value is used in the campaign URL. For example: <code>http://www.example.com/campaign/XXX</code> where <code>XXX</code> denotes the encoded string.</p>
  
  <p>On the server, the encoded string is decoded and decrypted. The resulting tracking values are used to track the incoming campaign link, and finally the server redirects to the destination URL with a HTTP 301 redirect.</p>
  
  <p>My questions are:</p>
  
  <ol>
  <li>What is the effect of this approach on SEO?</li>
  <li>Should I add keywords of the destination URL in the campaign URL?</li>
  <li>What about the redirect? What if the campaign URL is shortened with tinyurl.com for use on Twitter or Facebook? This results in a chained redirect (two subsequent redirects). Does this have a negative impact on SEO?</li>
  <li>Will my campaign URLs help for SEO or are there better ways to do this?</li>
  </ol>
  
  <p>Thank you.</p>