Understanding Persistent Cookie Matching in EventStream

[#1]

Persistent cookie matching in EventStream is an enhancement to ensure that third-party cookie sync data is saved in a Tealium-owned third-party cookie and included in all subsequent event collection requests.

In this article:

Table of Contents Placeholder

How It Works

Persistent cookie matching works in conjunction with cookie matching tags that run in iQ. Cookie matching tags make a request to a third-party vendor to retrieve a user identifier. The third-party vendor sends the anonymous identifier back to the Universal Data Hub (UDH) to be associated to the visitor. That visitor data is then returned back to the website through Data Layer Enrichment. This process allows server-side actions to tie visitors events across multiple domains.

Here's how it works:

• In iQ, a specific vendor cookie matching tag is added. When it runs in the page, it sends a request to the vendor asking for the visitor identifier and providing a return endpoint to which it can be sent.
• The vendor then makes a request back to the UDH with the requested identifier (cookie ID).
• In the UDH, the cookie matching request is received and the identifiers is saved to a Tealium third-party cookie.
• In subsequent EventStream events collected, the third-party cookie values are made available as event attributes. This process continues until the cookie expires.
  

  The Tealium Cookie Sync (TCS) cookie is valid for one (1) year, or when reaching the storage capacity of 4093 bytes.

  As an example scenario, the interaction between a TiQ cookie matching tag and the vendor might translate into something like this:
  

  Tealium Cookie Matching Tag:	“Hi, I’m Tealium, can you give me the visitor ID so that I can later tell you who this person is and something about them in a way you will understand?”
  Vendor:	"Sure. Here you go, this is the Visitor ID."
  Tealium Cookie Matching Tag:	"Thanks. I'll take the Visitor IDs you provided and persist them in the UDH. As useful data emerges, I'll leverage the data to your benefit and return it to you to use as needed."

Flow Diagram

The following diagram describes the flow of data between the Tealium UDH and the customer website.

1. Standard Event Collection
   The Tealium Collect tag fires for actions that do not need cookie sync data.
   No third-party cookie sync data is attached at this point.
2. Cookie Matching Requests (for each vendor)
   A cookie sync request is sent from the customer site to the vendor cookie matching service.
3. Cookie Match Response
   The cookie sync services sends a "302" redirect to the customer site.
4. UDH Saves Cookie
   The cookie sync redirect received by the customer site is forwarded to the UDH where the matched identifier is saved in the third-party Tealium cookie.
5. Tealium Third-Party Cookie Updated
   The UDH redirect back to the customer site sets the third-party cookie containing the synced identifier from the vendor.
6. Event Collection with Persisted Cookies
   The customer site then sends Tealium Collect tag requests that contain the persisted cookie data.
   The collect tag waits for all (or a percentage or preset delay time) cookie sync tags to complete and then fires again with third-party cookie sync data to ensure that actions that rely on visitor identifiers can fire.
   Third-party cookie sync data is attached at this point.
7. EventStream Actions
   In the final step, EventStream events now contain the persisted vendor identifiers as event attributes, which are then available to be mapped in connector actions.

Supported Marketplace Tags

The following table lists the callback method and callback formatting for Tealium marketplace tags that support the persistent cookie matching service:

Callback Method	Callback formatting	Tag Name
Calls Visitor Data (vdata)	Uses a callback to make the vdata call. (u.callback, query param with callback name, takes a cookie value and sends it to vdata)	Criteo Cookie Matching Service IBM UBX Cookie Matching Service intelliAd Cookie Matching Service Krux Cookie Matching Service Yahoo Cookie Matching Service (Hidden) The Trade Desk Cookie Matching Service
	Formatted (their url+vdata+query params)	Zandr (formerly AppNexus) Cookie Matching Service Google Analytics Cookie Matching Service Krux Cookie Matching Service Sizmek Cookie Matching Service
Does not call vdata	Copies an ID from one cookie to another	Adobe Analytics Cookie Matching Service Centro Cooking Matching Service DataXu Cookie Matching Service Google Cookie Matching Service for Doubleclick LiveRamp Realtime IdentityLink Pixel (formerly LiveRamp Cookie Matching Service) MediaMath Cookie Matching Service RadiumOne Cookie Matching Service Tapad Cookie Matching Service

Add a Cookie Matching Tag

Use the following steps to add a cookie matching tag:

1. Log into iQ Tag Management (TiQ).
2. In the left sidebar, go to the iQ Tag Managment > Tags.
3. Click + Add Tag.
4. In the left panel, click Cookie Match.
   A list of available marketplace tags supporting the cookie matching service displays.
   
5. Click + Add next to the tag you want to add.
6. Follow the onscreen instructions to configure your tag.
7. Save and publish your changes.

FAQs

How do I update my tag to get the latest functionality?

To verify that your tag is the latest version and contains the latest functionality, click on the tag and view the Tool Tips section in the left navigation panel. The Tips section will contain a notification if a newer version of the tag is available and instruct you to disable the current version and add the new tag from the tag marketplace.

Learn more about adding and configuring tags from the tag marketplace.