Google Tag Manager | Web Analytics

Advantages and Downsides of Server-Side Tracking

In our previous post about Google Tag Manager’s Server-Side Container (SSC), we started to look at how it works. We also compared various tools for server-side tracking. In this post, we look at some key advantages and some potential downsides that the Server-Side system will give you. We also draw a comparison with client-side tracking in each of these points.

Advantages of Server-Side Tracking

When it comes to the advantages, Server-Side Tracking has several major ones that for the most part have to do with control over and flexibility with the data you are collecting. This impacts how you can comply with various data laws, keep your and your users’ data safe, ensure the most accurate data possible, decide how and where data goes and potentially make your site perform better.

1) Data Quality

Server-side tracking offers significantly improved data quality compared to the client-side approach. While client-side tracking collects data directly from the user’s browser, browser restrictions and extensions such as ad blockers can impair data collection. This often leads to incomplete or distorted data, which is a significant disadvantage, especially in marketing. Server-side tracking bypasses these restrictive measures as the data is collected in a first-party approach and is therefore less susceptible to such interference.

2) Compliance

By intercepting data, the Server-Side Container can modify the data before it is sent to the final destination. This has great benefits for GDPR compliance, and similar privacy protections, as you can remove any information that could be used for profiling and fingerprinting before it arrives at the end destination.

The servers that the Server-Side Container functions on can be specified to a location. Therefore, this identifiable data does not need to leave the territory it was collected in (the EU most importantly for GDPR) before being removed.

In comparison, client-side tracking does not offer the possibility of changing data before it arrives at the analytics server, which significantly reduces data protection. In the case of Google Analytics, Google would have data control and unrestricted access to personally identifiable information.

Note though that manipulating and removing identifiable data may prevent some information from showing in your tools. For instance, removing or masking the users IP when sending data to Google Analytics may mean that no location data can be captured.

3) First Party Cookies

As the data is being transmitted through the Server-Side Container, modifications can be made to the data that is being returned to the site. As such, it can change the domain on which your particular tool’s cookies are set. It can set the cookie on its own domain. This means that browsers that limit or block the setting of third-party cookies will not expire prematurely or block the cookie from being set.

In contrast, many client-side tracking tools are based on third-party cookies, which are increasingly being restricted by browsers. This point becomes particularly relevant with the current changeover of Google’s Chrome browser, which is the last major browser to restrict the use of third-party cookies. First-party cookies through server-side tracking therefore offer a more reliable and future-proof solution for data collection.

4) Collect Data for One Tool and Deliver it to Others

When data is sent from the website, it may be intended for one tool but could be parsed and sent to others. This could be incredibly helpful in a number of cases. An example of this would be to reuse an incoming purchase event from a Google Analytics 4 request for Meta without loading multiple trackers on the client side.
In comparison, with client-side tracking, different trackers are loaded with different scripts in the browser. Each of these scripts must then process a purchase event and forward it to the respective Analytics server.

5) Client-Side Load Reduction

As described in the previous point, shifting a large part of the data processing to the server-side container can reduce the website loading time for users.
Client-side tracking in turn reduces the performance of the website, as data processing and data transfer are also handled by the browser.

6) Hiding API Keys and Client Secrets

The Server-Side Container is the only place where data can be sent to the final tool, so all API keys and client secrets can be kept there. This avoids any chance of these being exposed on the client side. An example of this is the Google Analytics GA4-Measurement ID. A third party can go to any site running Google Analytics and simply take the GA4-Measurement ID off the site, put it on another, and spam the Google Analytics account. We have seen this often happen over the years. Through Server-Side Tracking this would not be possible as the GA4-Measurement ID can be added only on the server side and so won’t be exposed at all when the website loads.

In contrast to server-side tracking, with client-side tracking all information is transmitted transparently in the browser. This can lead to problems in many respects. One example from a marketing perspective: users can block or manipulate tracking with the help of browser extensions or private browsing modes. This creates gaps in the data, which can lead to incomplete analyses and less effective marketing campaigns.

7) Load the Tracking Script from Your Own Domain

When loading the tracking script from your own domain, server-side tracking offers numerous advantages over client-side tracking from a marketing perspective. As the tracking script is loaded directly from your own domain, it is treated as a first-party script and can bypass many browser restrictions and blockers that often affect third-party scripts. This results in more reliable and complete data, as less tracking data is lost. Another advantage is that traffic and user data can be more tightly controlled and better protected.

Setting up such a server-side tracking system requires a certain amount of technical expertise. Companies must have the necessary technical know-how or seek external help to successfully implement and manage this setup. In comparison, client-side tracking is easier to set up, but more prone to data loss and inaccuracies due to browser blockers and user privacy measures.

8) Data enrichment on the server side

A comparison of server-side tracking and client-side tracking reveals a further advantage of server-side tracking in the area of data enrichment. With the client-side setup, there is no possibility of further processing the data stream or enriching it with additional data. This is particularly relevant for e-commerce companies: Product data does not have to be stored on the website, but can be stored in databases. With server-side tracking, this data can then be linked to the website’s tracking data before being sent to the analytics server. This leads to a performance boost, as the website itself has to process less data.

An additional advantage for online marketing is that more detailed and accurate reports can be created by enriching the data on the server side. This gives marketers deeper insights into user behavior and the performance of individual products. This precise data makes it possible to develop more targeted marketing strategies and create personalized campaigns that are better tailored to the needs and preferences of customers.

Disadvantages of Server-Side Tracking

There are a handful of disadvantages and scenarios to Server-Side Tracking that you should be aware of. These points are either about the extra lifting it takes to run the Server-Side Tracking as well as some of the pitfalls of being more responsible for your own data’s accuracy and your user’s privacy.

1) Technical Expertise

Although there are now several providers for the server-side approach, making it easier to set up, server-side tracking still requires a higher level of technical understanding. There are still some technical hurdles to overcome, such as setting up and configuring the servers, connecting to the website and the tagging itself. In comparison, the integration of client-side tracking is very simple and quick to implement.

2) Data Accuracy Depends on You

If you are coding a client or tag, then the responsibility for making sure that data reaches its destination in the correct format is down to you and your code. This means there is some added room for mistakes to occur. You are also responsible for ensuring that the data sent is legally permitted to be sent.

3) Cost

In contrast to the client-side approach, there are costs associated with a server-side setup. Many tools now offer all-in-one packages in which both server and service are sold together. JENTIS, Stape.io and Fusedeck are examples of this. These packages can make setup and administration much easier by offering a comprehensive solution from a single source. Nevertheless, a server-side approach remains more cost-intensive than client-side tracking. The costs arise from the server infrastructure required for operation, as well as the need for redundancy and sufficient capacity. The more servers are required and the larger the data volume, the higher the running costs. Despite these additional expenses, the server-side approach can be worthwhile due to the improved data quality and increased flexibility.

4) Privacy Concerns

We have already touched on this but a concern with Server-Side Tracking is that it makes it easier to circumvent some of the measures your users put in place to prevent tracking. It is important to make sure that user’s privacy decisions are respected and that the relevant laws and regulations are abided by.

In contrast, client-side tracking offers hardly any opportunities to implement these requirements, as tracking takes place directly in the user’s browser and the data is forwarded directly to the respective analytics server.

In case you would like to learn more about Server-Side Tracking for your website, send us a message, and we will gladly get back to you to discuss your individual requirements.

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