Why the Client-Server Model for Tag Management is Going Obsolete
Those who follow the constant evolution of digital marketing have probably noticed that tag management is repeating many of the same lessons learned by the web analytics community over a decade ago. In the early days of web analytics, the prevailing debate was “tags vs. logs.” As the sector started maturing, the marketplace picked the ultimate winner.
Log-based vendors relied on server logs for their data collection whereas tag-based solutions like Omniture and WebSideStory (both now part of the Adobe Marketing Cloud via acquisitions) relied on tags for data collection. Tags provided better data because they collected the data from where it mattered most: directly from browsers of site visitors. Getting the data from the source allowed for more accurate and timely data collection and as a result, log-based solutions fell by the wayside in favor of tag-based ones. By 2002, all new vendors realized the benefits of the tag-based approach and adopted this methodology. Tags won.
What does this have to do with tag management? Well, it turns out the tag management space is currently going through a similar debate. The debate of the client-side vs. the client-server method.
The client-server model works by making a server-call on each page to an application server. The job of the application server is to decide which tags need to be loaded on which pages. A request is then sent back to the web client, instructing it to load the appropriate tags.
The Market is the Ultimate Judge
While vendors from each side can boast about their architecture and methodology, there’s one fact that cannot be disputed and clearly states why the client-server model is becoming obsolete. In the last two years, many vendors have entered the space and not a single one has adopted the client-server model. New vendors have the advantage of studying existing vendors and adopting the best technology. In all cases, new tag management vendors have adopted the client-side methodology. Think about it. Those who know the space the most and are banking millions of dollars – vendors – are all adopting the client-side approach.
But why are new vendors, after careful analysis of the market, deciding to adopt the client-side methodology? The reason is that client-side is better, faster and more stable than its client-server counterpart. Here are some of the high-level advantages.
Client-side is Where the Data is
Reduced Point of Failure
One of the many advantages of the client-side model is that it can completely eliminate the application server call altogether. The application server call is an additional point of failure that’s introduced on every page. Imagine having to make a round-trip call on every single page view for every single visitor just to determine which tags to load? This is both an extra step and a point of failure that’s introduced on every single hit. It’s not efficient.
Client-Side Logic is Faster
Those still supporting the client-server model are defending it by making claims, some of which are listed here.
- File Size
- Campaign Visibility
- Client-Side is a Container Tag
Another misconception in the market is that client-side solutions are tag containers. The idea behind a tag container is that all tags are placed in a container and all tags load regardless of the rule. This is absolutely untrue and reflects the lack of knowledge by those making the claim. Deep conditional logic can be placed for each tag. For example, a Google AdWords tag can be programmed to load on the confirmation page only if the traffic came from AdWords.
Another common but incorrect assertion is that the client-server model is better suited for running testing tool in a ‘flicker-free’ fashion. This is false. You can easily use the client-side model to run testing tools such as Adobe Test & Target in a flicker-less mode. In fact, we recommend you download our new white paper on this topic, “Improving Testing & Optimization through Tag Management,” to learn more about our testing deployment capabilities for yourself.
What About the Server-to-Server Model?
History Repeating Itself
The web analytics space carries many lessons with it that apply to what is currently taking place as a debate in the tag management space. Key among them is the type of technology adoption by vendors. By following the vendors, the market can clearly see which methodology is winning due to its superior capabilities and benefits. Just as web analytics vendors abandoned log-based systems in favor of using tags for data collection over a decade ago, we’re seeing tag management vendors adopting the more data-centric client-side methodology. These are clear signs that the client-server model will become obsolete in the not-so-distant future.