What Is Caching Data?

What is caching data and how does cache work? Caching Data is a process that stores multiple copies of data or files in a temporary storage location—or cache—so they can be accessed faster. It saves data for software applications, servers, and web browsers, which ensures users need not download information every time they access a website or application to speed up site loading.

Cached data typically includes multimedia such as images, files, and scripts, which are automatically stored on a device the first time a user opens an application or visits a website. This is used to quickly load the application or website’s information every time the user subsequently opens or visits it. Caching is a good solution for the von Neumann bottleneck, which looks at ways to better serve faster memory access.

A Domain Name System (DNS) caches DNS records to perform faster lookups, content delivery networks (CDNs) use caching to reduce latency, and web browsers cache requested Hyper Text Markup Language (HTML) files, images, and JavaScript to load websites faster. For example, when a user visits a website for the first time, an application or browser retains information to help them access it faster and more efficiently.

Cached data works by storing data for re-access in a device’s memory. The data is stored high up in a computer’s memory just below the central processing unit (CPU). It is stored in a few layers, with the primary cache level built into a device’s microprocessor chip, then two more secondary levels that feed the primary level. This data is stored until it's time to live (TTL), which indicates how long content needs to be cached for, expires or the device’s disk or hard drive cache fills up.

Data is typically cached in two ways, through browser or memory caching or through CDNs.

1. Browser and memory caching: Memory caches store data locally on the computer that an application or browser runs on. When the browser is active, the resources it retrieves are stored in its random access memory (RAM) or its hard drive. The next time the resources are needed to load a webpage, the browser pulls them from the cache rather than a remote server, which makes it quicker to retrieve resources and load the page.
2. CDNs: Caching is one job of a CDN, which stores data in geographically distributed locations to reduce load times, handle vast amounts of traffic, and protect against cyberattacks. Browser requests get routed to a local CDN, which shortens the distance that response data travels and transfers resources faster.

When a user visits a new website, their browser needs to download data to load and display the content on the page. To speed up this process for a user's future visit, browsers cache the content on the page and save a copy of it on the device hard drive. As a result, the next time the user goes to that website, the content is already stored on their device and the page will load faster.

Cache memory offers extremely low latency, which means it can be accessed quickly. As a result, it speeds up loading the second time a user accesses an application or website. However, a cache cannot store a lot of memory, so it only stores small files like images and web text.

Data can be cached in many ways, but it is typically reliant on the website’s owner to set a "header," which tells a device that data can be cached and for how long. This instructs a user’s browser what information to download and where to store the temporary files. The user can then create policies and preferences around what data they cache and even clear their whole cache to reduce the amount of data stored on their device.

Caching data is important because it helps speed up application performance and increase efficiency. It stores data locally, which means browsers and websites will load faster because access elements such as homepage images have previously been downloaded.

Internet users will typically leave a website that loads too slowly, which makes caching vital for website owners to improve user experience and encourage people to use their site. It is also important for online tools like Google Docs, which enable users to access and save their documents online.

However, there are downsides to caching data. Caching can improve browser performance, but it also risks users’ confidential or sensitive information being exposed to cyber criminals. Caching data could result in authentication data, browsing history, or session tokens being vulnerable, especially if a browser is left open or if another user has access to it.

FortiGate next-generation firewall (NGFW), can help identify and block attacks that occur on a network. This can be useful for protecting the cached data stored on users’ devices by blocking attackers from gaining access. 

The Fortinet NGFW solutions update as the threat landscape evolves, which ensures that businesses are always protected against the latest attack vectors and malware strains. It also integrates with other Fortinet solutions like FortiGuard and FortiSandbox, which keeps businesses safe from known and zero-day threats.

A simple cache definition is a temporary storage location that stores data, files, and login details for applications and websites on a device’s memory.

Clearing the cache is the process of a user deleting data and files stored within their cache folder. 

Yes, deleting the cache frequently can help users clear up storage space on their device. However, users must be careful about the data they delete. Clearing the cache may slow down page load times and remove important data and required website logins.

A cache stores data in a local folder on a device. This can increase application or website performance and efficiency by speeding up load times the next time a user opens or visits an application or site.