Server-side Tagging

With the advent of new and shifting privacy regulations and cookie extinctions, data gaps and governance issues will be major challenges for marketing teams. Server-side tagging addresses many of these issues from a technical standpoint. We believe Server-side Tagging is fundamental for any business that needs measurement of their website moving forward.

What Is Server-side Tagging?

Server-side Tagging or Google Tag Manager (GTM) Server is the fifth container type of Google Tag Manager. Earlier versions are GTM for browsers, Accelerated Mobile Pages (AMP), Android, and iOS. As the name alludes to, GTM Server runs in a server environment, in contrast to the other container types which run in the users’ client, i.e. browser or mobile app.

GTM Server is a system that enables the collection and distribution of visitor data in a more protected and secure way, without relying on JavaScript cookies. In a nutshell, it receives data from a client; the data can then be shaped and filtered before it is sent on to external marketing and analytics servers.

It is most straightforward to set up a GTM server in Google Cloud Platform (GCP) but it can also be implemented with other cloud providers, or even on a local server.

How It Works

A website will typically have multiple marketing and analytics services implemented. These services each have scripts running on the website that sends data streams back to the vendor, data such as a page was viewed, or a button was clicked.

By utilizing GTM Server, only one data stream from the client is needed, instead of multiple ones for each vendor. The data is sent to the GTM Server endpoint and then forwarded to the services you use, such as Google or Facebook. In other words, it functions as a proxy or middleware between the data collected from the browser or device and the marketing or analytics tools.

What Are The Main Benefits?

Data Governance

There is a growing concern regarding how the marketing and analytics vendors handle the data they collect, both on their platforms and the websites that utilize their services. With GTM Server, they will never receive direct requests from your visitors. They’re only receiving requests from the server and the data you choose to forward.

Only the site owner has access to the data in the server until they choose to send it elsewhere. Site owners have full control over how the incoming data is shaped and where it’s routed from the server.

For example, data such as incoming IP addresses and other identifiers from site visitors can be encrypted or redacted before being sent to third-party tools with servers in the US.

Data Accuracy

In recent years, most browsers have made concerted efforts to ensure the privacy of their users. Apple has been prominent with its Intelligent Tracking Prevention (ITP), which among other things limits how long cookies and cookie-like technologies are stored in Safari. Cookies set with JavaScript are removed after seven days of inactivity by visitors and mere 24 hours if the traffic originated from ad platforms.

Google Analytics and other services set their cookies using JavaScript. When they are removed, it affects metrics such as new vs. returning users and conversions by traffic channels.

Using GTM Server, HttpOnly cookies can be set instead of with JavaScript. These cookies are not subject to ITP and thus not deleted. This allows tracking to be dramatically improved and ensures better marketing optimization and remarketing capability.

Site Performance

When you move 3rd party tags to a server environment, it takes the burden and heavy lifting away from the website. Less code is being executed when customers visit your site, leading to faster page load times and better site performance. Important to note is that faster loading time and site performance are Google ranking factors nowadays.

In Summary

Server-side tagging has significant benefits, both from a business value perspective and data control and governance standpoint.

Business value is ostensibly generated by moving from JavaScript cookies to server-side (HttpOnly) cookies. By prolonging the expiration time of cookies with GTM Server, we improve attribution, remarketing, and A/B test capabilities.

Moving to a server-side tagging process does not remove the requirements to manage user consent and privacy regulations. But it does provide a staging environment for your data with control mechanisms as to what and where to send that data forward.

If you want to learn more about Server-side Tagging, feel free to reach out to us.

Ted Solomon


[email protected]