When a web API is not designed to store information from a client request on the application server, we can call it a Stateless API. In this API architecture, each independent client request to an application server contains all the information it needs to interact with server resources, making the retention of the client state unnecessary. Stateless APIs are one of the selling points of Representational State Transfer (REST) API architecture - a key building block of modern distributed application architecture.

In contrast, when a web API is designed to store information from each client request on the application server, we can call it a Stateful API. Maintaining the state of a client request makes it possible to reference details from that request throughout a prolonged session of server access. Stateful API architecture is commonly utilized, for example, in the context of Simple Object Access Protocol (SOAP) APIs, where data-retention concepts like session management – a sequence of interconnected server requests – are deemed important to the function of a given application.

What are the advantages of stateless APIs?

Stateless APIs effectively decouple clients from the application servers they seek resources from, simplifying the relationship between the two. Because stateless API servers aren’t concerned with caching existing client information and/or synchronizing data between servers, consecutive requests from a single client – as well as simultaneous requests from dozens of clients interacting with a single server resource – can be evenly spread out over multiple application servers with load balancers. Applications utilizing stateless APIs can therefore scale exceptionally well with steady increases in client traffic.

We encounter stateless APIs constantly in our interactions with everyday web applications, such as when we browse movie categories through a streaming platform or look at products on an ecommerce website. In both of these basic examples, our initial and subsequent requests for layered server resources are performed independently of one another, and our requests can be fulfilled across multiple different servers as server traffic fluctuates.

Stateless APIs no longer offer an advantage when maintaining user state is a requirement, as is the case – for example – with user authorization portals in secure online banking applications. In such cases, client-supplied data (i.e., login details) is required to maintain a secure session with the application server, tying the client and the server together for the remainder of the session.

Stateless Cloudmersive APIs

All Cloudmersive APIs are designed with enhanced performance and security features. They’re all stateless, with requests processed in-memory (when the request is complete, the memory is released). Additionally, Cloudmersive does not store any Customer Payload Data, and it utilized strong encryption algorithms both in transit AND at rest.

For more information about Cloudmersive APIs, please do not hesitate to reach out to a member of our sales team.