Understanding the Problem

In this episode, let’s discuss what the problem is with using URL query string. It’s important for you to understand the problem first in order to solve it. Right? Do this episode before you move on.

Let’s start by analyzing the speed of this lab using Pingdom’s website speed test. Here’s a link to the test that I ran.

Running the test, it explains why it scores query strings:

Resources with a “?” in the URL are not cached by some proxy caching servers.

Therefore, the problem is that some proxy caching servers may not cache the resources. That means anything connected to those servers are not benefiting from caching.

NOTE: Browsers still can locally cache.

What is a “Proxy Server”?

In this episode, I explain what a proxy server is as well as why we should care about a proxy being able to cache our website’s assets and resources.

I reference this article on MaxCDN’s blog: What is Proxy Caching?. I recommend that you read this article to understand the problem further.

The Problem

The problem is not the score or trying to get a better score on a site like Pingdom. Rather, the problem is:

While they can cache locally, their network is not benefiting from centralized caching to deliver an even faster experience.