# Retargeting Unknown Visitors With Google Display Video 360

Cookie Sync is a common technique for retargeting unknown visitors via the Ads platform. This document describes how Cookie Sync works between Treasure Data and Google Display & Video 360 (Google DV360).
Since 2021, Google has required customers to store the mapping/syncing of a td_global_id to Google's cookie ID in Google DV360. You'll use Treasure Data JavaScript SDK to upload a synced Treasure Data's td_global_id with Google Cookie to your Treasure Data account.

**Example**

A website visitor is assigned td_global_id *123* on a customer's website, while the visitor is also assigned a Google cookie ID *ABC*. The CDP must inform Google that Google's *ABC* and TD's *123* are the same visitor.

This topic contains:

* [Implementing the Synchronization Process](#implementing-the-synchronization-process)
* [Synchronization Endpoint Sample](#synchronization-endpoint-sample)
* [Set up Segmentation](#set-up-segmentation)
* [Set up Google Display & Video 360 Authentication](#set-up-google-display--video-360-authentication)
* [Set up Activation](#set-up-activation)


# Implementing the Synchronization Process

![](/assets/overview.69605299a336eb7722a74f0b4565a62113188b02b49d6fe4a2f1c17844974216.ad50cbca.png)

## Synchronization Endpoint Sample

Prepare the synchronization endpoint using TD JS SDK and populate the correct URL values.

`https://cm.g.doubleclick.net/pixel?google_nid=treasuredata_dmp&google_hm=NThkOTVmNDAtMzAyOS00Y2FkLWIxYWQtM2ZlYWVmNzE5Njhk`

* google_nid: 'treasuredata_dmp'
* google_hm: base64-encoded td_global_id value


Ref. [https://developers.google.com/authorized-buyers/rtb/cookie-guide](https://developers.google.com/authorized-buyers/rtb/cookie-guide)

Prepare a pixel tag to track the td_global_id with Google Cookie

The following code includes a sample tag for synchronizing and tracking the td_global_id with Google Cookie via pixel tag.


```html
<script type="text/javascript">
!function(t,e){if(void 0===e[t]){e[t]=function(){e[t].clients.push(this),this._init=[Array.prototype.slice.call(arguments)]},e[t].clients=[];for(var r=function(t){returnfunction(){return this["_"+t]=this["_"+t]||[],this["_"+t].push(Array.prototype.slice.call(arguments)),this}},s=["blockEvents","unblockEvents","setSignedMode","setAnonymousMode","fetchUserSegments","resetUUID","fetchServerCookie","addRecord","fetchGlobalID","set","trackEvent","trackPageview","trackClicks","ready"],n=0;n<s.length;n++){var c=s[n];e[t].prototype[c]=r(c)}var o=document.createElement("script");o.type="text/javascript",o.async=!0,o.src=("https:"===document.location.protocol?"https:":"http:")+"//cdn.treasuredata.com/sdk/3.0/td.min.js";var a=document.getElementsByTagName("script")[0];a.parentNode.insertBefore(o,a)}}("Treasure",this);
    
// Generate a pixel tag for Cookie Sync
function googleSyncCallback() {
  td.fetchGlobalID(
    function(global_id) {
    	var gidsync_url = 'https://cm.g.doubleclick.net/pixel?';
    	var params = [
    		'google_nid=treasuredata_dmp',
    		'google_hm=' + btoa(global_id)
    	];
    	var img = new Image();
    	img.src = gidsync_url + params.join('&');
    	document.body.appendChild(img)
      }
    );
  }
    
  // Generate a general tracking tag
  var td = new Treasure({
    host: 'in.treasuredata.com',
    writeKey: '<YOUR WRITE ONLY KEY>',
    database: '<Your target Database>',
    startInSignedMode: true
  });
  var tbl = 'cookie_sync_table';
  td.set('$global', 'td_global_id', 'td_global_id');
    
  // Syncted google_hm and td_global_id require to be a same value.
  td.trackPageview(tbl, googleSyncCallback);
</script>
```

## Set up Segmentation

[Set up segments](/products/customer-data-platform/audience-studio/segment/segments-overview) in TD Audience Studio to support your requirements.

## Set up Google Display & Video 360 Authentication

You can authenticate Google Display & Video 360 Authentication by Google Partner ID or Google Advertiser ID. These are related but not identical concepts:

* Google Partner ID is for the enterprise customer of the DV360 platform.
* Google Advertiser ID is for a particular brand.


![Information](/assets/info.aa88698bdb590fb167080bc7bc900e461aa937f4b3774de0759e678e7a8aab37.ad50cbca.png) | Different outside ad agencies might manage the marketing and ads if a customer has multiple brands. So each brand may have a unique advertiser ID assigned, while the customer has a single Partner ID.

---|---

## Set up Activation

Set up your activation as follows.

![](/assets/image2023-5-22_15-8-33.a95b103d9914ec9b47a92983706e0c43ee559800843036abf60453e6a10c6487.ad50cbca.png)

| Field | Values | Description |
|  --- | --- | --- |
| Source column name mappings | cookie: cookie,list_name:list_name | The left side of the colon is Google's expected attribute, for example, cookie: or list_name: |
| The right side of the colon is the designated attribute name in the Activation. The value names are arbitrary. |  |  |


![](/assets/image2023-5-22_15-55-12.029a9002378a024dea0f633690807c41d1b10d5bff9659f10227b6834a50a620.ad50cbca.png)

Field| Values| Description|
---|---|---|---
Column Mapping| Source: td_global_id
Output Column Name: cookie| The value is the data point that should be used as the cookie.

| ![Information](/assets/info.aa88698bdb590fb167080bc7bc900e461aa937f4b3774de0759e678e7a8aab37.ad50cbca.png) | The Output Column Name displays on the Details tab. |
|  --- | --- |


String Builder| String: xxx_DV360_Test_v2
Output Column Name: list_name|  |  ![Information](/assets/info.aa88698bdb590fb167080bc7bc900e461aa937f4b3774de0759e678e7a8aab37.ad50cbca.png) |  The Output Column Name displays on the Details tab.
---|---