Need some undertanding of multi level cache scenario

Question

I am well aware of how to use cache for mysql(using views and few other technology), Php(Using Smarty), web pages(Writing web pages once for a limited time and loading them whenever is required).

Now I have come across this term called Multi-Level cache which i think I am not aware of it.

It will be great if someone can give me a head start on it.

I am not asking you to give complete details at all.

Few bullet points will be enough.

I have researched on google and did not find a good article.

Any help is much appreciated.

Answer 1

Here is a small info on the Multi-level caching

A multilevel cache spreads the cached data contents across several servers across the network.

1. The top level caching server holds the most commonly accessed pages, and the lowest-level caching server holds the least commonly accessed pages.
2. The various levels combine in a network of cache servers called a Web caching mesh.
3. The caches communicate among themselves, using HTTP and special cache-coordination protocols, to divide the contents appropriately and maintain consistency among the servers

More info can be referred to here, here, here and here