Cookie Sync process

Why we sync?

The user ID matching process between the DSP and the SSP happens through a process called cookie syncing. Cookie syncing is necessary because web servers of any kind can only request cookies that are set to their own domain.
Cookie syncing is an essential part of digital advertising that allows a DSP (aka buyer) to obtain the information that will allow them to serve the most appropriate advertisement. Thus, it is important to be sure that DSP's and SSP's cookie ID's are appropriately synced.

Cookie syncing types

Cookie syncing can be of two types: SSP initiated or DSP initiated, both of which can be active at the same time. To maximize the number of bid requests with a pre-matched Cookie ID, the 2-way syncing (both SSP and DSP) should be enabled.

DSP initiated cookie syncing

(1) DSP places their Sync URL on the browser via the display, video, etc.

(2) DSP then redirects to the SSP Cookie Sync URL like

ssp-example.com/sync?dsp_id=XXX&user_id=[[USER_ID]]

This requires SSP to provide DSP with their, DSP, unique buyer ID (URL parameters are like dsp_id, buyer_id, adv_id etc.).

(3) SSP will then set an SSP cookie on the browser or modify an existing one with the DSP USER_ID and/or USER_DATA.

SSP initiated cookie syncing

(1) SSP places the DSP Sync URL on the browser

(2) and initiates an HTTP GET request to the DSP Sync URL

(3) This requires DSP to provide SSP with a DSP Sync URL like

px.adhigh.net/p/cm/{SSP_ID}

The DSP then redirects the client to the SSP Cookie Sync URL (see DSP initiates cookie syncing section above)

(4) SSP will then set an SSP cookie on the browser or modify an existing one with the DSP USER_ID and/or USER_DATA.

Cookie syncing parameters

In order to have the cookie sync implemented, we need to configure its settings on our side. We would appreciate your cooperation in answering additional questions from the questionnaire we've sent to you recently. 

Those may include, but are not limited to the following:

• Can you initiate the sync on your side?
• Can you store matching on your side?
• How often do you refresh cookies? (in days)
• Other

Also, providing any available cookie sync documentation would be a great help for us as well.