What is CDN caching?
CDN is a network of servers also known as a content delivery network. It is a series of proxy servers placed all over the globe. The servers store images, videos, graphics, and web pages. The CDN closest to the website owner stores all your data. These are called proxy servers closer to the website owner than the origin server. Some search engines cache websites as well to deliver results faster.
What is a proxy server?
The proxy server receives a request from the client the message is sent to interconnected proxy servers, and the information is retrieved quickly by the client requesting from the nearest proxy server. This information retrieval is faster when website owners host their property on CDN. The benefit is not having to travel to the main showroom the product is available from the nearest one. Thus, information retrieval takes minutes rather than hours. Thus, CDN makes a cache of the web pages and stores them to the nearest proxy server. Thus the content delivery network retrieves information more quickly.
When a user requests content from a website using a CDN, it fetches and stores information at the nearest server the content remains in the proxy cache as long as users continue to request it.
What is a CDN cache hit?
A cache hit is when a client device makes a request and successfully retrieves information that is known as a cache hit. This means the content was saved successfully. In this case, the retrieval will be faster.
What is a cache miss?
When CDN fails to retrieve the information it means that the content has been saved improperly. This is known as a cache miss. Usually, in the case of a catch miss the origin server has to respond to fetch information if it has been properly stored.
Where are CDN caching servers located?
As mentioned earlier CDN proxy servers are located in data centers all over the globe. Cloudflare has CDN servers in 285 cities. This keeps its servers closer to the end user. How long does cached data remain in a CDN server?
Website owners attach TTL with their content when TTL expires the data is no longer in the CDN Store. The TTL is stored in a part of the response called the HTTP header, and it specifies for how many seconds, minutes, or hours content will be cached. Uncalled-for information or one not in demand will be removed and on some basis, CDN removes information manually.
How does Cloudflare use caching?
Cloudflare has 202 proxy servers spread all over the globe. Cloudflare offers free CDN caching services, while paid CDN customers can customize how their content is cached.