This method enables your site to directly and securely make requests to theEdge Decider making it the quickest and simplest way to get started with Optimizely Performance Edge.

How Edge Subdomain works

1. A script on your site initiates a DNS lookup to your custom subdomain (for example,optimizely.customer.com).

2. Your DNS provider tells the visitor’s browser to send the request tocname.optimizely-edge.com because of a CNAME record that aliases your subdomain tocname.optimizely-edge.com.

• You’ll need to add thisCNAME record as part of the implementation.
• If you define aCAA record on your domain, make sure itallows DigiCert or Let's Encrypt as a CA. If your domain does not allow either CA, then you will need to use aCDN Proxy implemntation.

3. The Edge Decider processes requests sent tocname.optimizely-edge.com and returns a microsnippet that runs on your site to apply your experiments.

• See the documentation onHow Optimizely Performance Edge works for the full details of what the Edge Decider does and what it returns.

What about a direct request to cname.optimizely-edge.com?

The reason the script needs to make a request to your custom subdomain as opposed tocname.optimizely-edge.com directly is to let Optimizely Performance Edge access cookies on your site. The list of cookies that Optimizely Performance Edge reads can be found in theCookies and localStorage in snippets documentation.

If you target an audience based on cookie values, the Edge Decider needs access to those cookies as well.

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Note

Onevery request to a particular domain, browsers sendall cookies that that domain has access to. What this means is that using your subdomain to make the request gives Optimizely’s Edge Decider access toall the cookies that your subdomain has access to.

Optimizely Performance Edge only reads from the cookies listedhere and any cookies that you target an audience with.

Though (with the exception of the cookies listedhere) Optimizely Performance Edge does not store or modify any cookies you send to the Edge Decider, we recommend limiting the cookies that your subdomain has access to as much as possible and ensure that no direct personal identifiers (e.g. name, email, address) are included in cookies sent to Optimizely.

• You can prevent cookies from being sent bynot scoping these cookies to your chosen subdomain (e.g.optimizely.customer.com) or parent domain (e.g.customer.com) of your site.

If you have concerns with granting Optimizely Performance Edge access to the abovementioned cookies, we would recommend implementing Optimizely Performance Edge using aCDN Proxy where you have the ability to control which cookies are included in or excluded from the Optimizely Edge Decider request.

Implement the Edge Subdomain

1. Add aCNAME record at your DNS provider to create an alias from your selected subdomain (for example,optimizely.customer.com) tocname.optimizely-edge.com.

2. Contact your account team and let them know you are interested in implementing Optimizely Performance Edge through the Edge Subdomain.

• Let them know which subdomain you would like to use to make requests from (like,optimizely.customer.com).
• Optimizely's prepares the infrastructure to securely receive your requests from your subdomain.

3. Your account team tells you when Optimizely is ready to receive your requests. This can usually be done within two business days.

4. when you hear from your account team, you should implement the Edge script tag on your site. You can generate this script tag in your Project Settings.

The script tag should look similar to the following:
<script src="https://optimizely.customer.com/edge-client/v1/1234567/6543210" referrerpolicy="no-referrer-when-downgrade"></script>

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Note

Thereferrerpolicy attribute is required in your script tag to let Optimizely Performance Edge receive the referrer for page targeting purposes.

Starting inChrome 85, Chrome will default to using thestrict-origin-when-cross-origin referrer policy which would prevent Optimizely Performance Edge from getting the full URL of the page the visitor is viewing. Other browsers have indicated they plan to follow Chrome’s lead in this as well. Setting the referrer policy to the current defaultno-referrer-when-downgrade resolves this.Learn more about these referrer policies.

For best performance, you should add the script tag at thetop of the<head> tag of the HTML document of the page you want to run Performance Edge on.

Also, donot include theasync attribute in your script tag or else your site is prone to flashing when the microsnippet response from the Edge Decider executes on your site.

<html>  <head>    <script src="https://optimizely.customer.com/edge-client/v1/1234567/543210"             referrerpolicy="no-referrer-when-downgrade">    </script>    <!-- Other Scripts  -->  </head>  <body>  <!-- Your Site Content -->  </body></html>

Verify your configuration

To verify your configuration and ensure that the correct data is received in the browser, start by checking that the Edge Decider returns a microsnippet to your browser.

1. Load the webpage that has the<script> tag on it.
2. In the JavaScript console, runoptimizelyEdge.
3. IfoptimizelyEdge returns defined, you have implemented Performance Edge successfully.

Updated 2 months ago