What is Origin Server?

The Internet is vast and ever-expanding, just like the Universe. Therefore nowadays, even a single connection to a website requires much more than a bunch of wires. And origin servers are one of the crucial elements of internet traffic.

What is an origin server?

An origin server is usually, but not necessarily a powerful computer and the software that runs on it. And it is a core of the CDN (Content Delivery Network). It is capable of listening and responding to incoming requests. It also stores and computes the key content from your website, like the original version of its HTML, CSS, or JavaScript files. For example, when a user authorizes their website account, the validation most likely goes through the origin server.

Technically, you can even use your PC to set up an origin server for a low-scale operation. Yet, origin servers normally have to handle a large number of requests. Load balancing and horizontal scaling usually help to maintain such a flow. And then, to eventually distribute and serve content to end users without delays, the Content Delivery Network support comes into place.

Origin server and the CDN

The Internet heavily relies on CDNs. If origin servers always were the only traffic providers, you would deal with significantly lower loading speeds. It would happen not only because of the server overload from all the requests but also because of the considerable network bandwidth. A way to avoid all of these issues is CDN.

CDN helps to take the load off the origin servers by dispersing the traffic flux. This is possible with the help of edge servers acting as nodes situated in geographic proximity to a user.

How does an origin server interact with edge servers?

The major support edge servers provide to origin servers is caching. Previously, after you established the first contact with an origin server, it would send a response not only to you but also to the edge server(s). After that, they would take on the role of storing the static content from your website. Nowadays they still do, but your request is sent directly to the edge server for it to load the cache. And, if there is a need, it would relay the request to the origin server. Such an algorithm is a great way to accelerate the loading speed. And hey, loading speed is a crucial aspect of increasing your website’s rank in search!

Images, video, PDF files, HTML, JavaScript files, and other content is the most memory-demanding part of any page. Some CDN providers, like us, focus on both caching and optimizing website content at the same time.

The origin server, in turn, keeps storing the original version of your website and its content. More importantly, they sometimes host databases for user authentication and contain key server-side code. Such practice is dangerous and crude, but unfortunately, it is still widely used.

Does CDN prevent origin servers from attacks?

CDN doesn’t make origin servers completely invulnerable, but it significantly lowers the security threat. And it helps to do it in three ways:

Hiding the origin server IP address

CDN nodes are capable of rerouting requests to be sent to their IPs while still sending them to the origin server. This way, in case of a DDoS attack the harmful traffic won’t be able to reach the origin server with its IP hidden behind edge IPs.

Dispersing requests

Even without targeted DDoS attacks, dangerous traffic spikes still possess a threat. For example, in some cases, the usage of a website might increase during certain times of the day. But thanks to CDN, all of this traffic will be routed through edge servers and prevent the website from overloading.

Inspecting incoming traffic

The initial examination of HTTP/S requests is done by edge servers. This is a great way to block DoS attacks, aimed at the origin server with an intention of rendering your service inaccessible.

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