When Should You Cache API Calls at the Edge?

When Should You Cache API Calls at the Edge?

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While the rise of consumer electronics has seen increasingly powerful solutions in place everywhere you look, this has also resulted in the tack-on effect of increasing data demands. And in most networks, this is challenging — even modern networks and systems must grapple with the fact that electrical signal transmission — or light-based solutions like fiber optics — are still limited by the laws of physics and the availability of affordable components.

In other words, we want to handle as much data as we possibly can — but that amount is growing almost exponentially.

One such solution is the concept of caching at the edge. Today we’re going to talk about how APIs can be used to cache at the end, and how they are used in the real world to great effect at orgs like Netflix, Sony PlayStation, and more.

Understanding the Process of Caching

Edge caching and server-side caching are really two sides of the same coin, and they both endeavor to answer the same question — in a reality where users are consuming ever-increasing amounts of data and performing ever-increasingly complex functions, how do you ensure rapid service, high availability, and strong security while balancing server and service resources. Caching is an answer to at least some of that question — by storing data or processes that are often utilized in a specific form and function for routine retrieval, you can prevent repeated database hits, serve content quicker, and ultimately have better control and visibility over the data flow.

Where this question becomes more complex is when you consider where that caching is happening. In other words, you could separate caching into a series of domains and impacts. Caching on the server side may serve data more efficiently while giving greater control to the server and the service provider, especially when it comes to security, but the delivery of content and systems to the user suffers the same latency it would in any typical deployment. The benefit is almost entirely for the server.

Browser-side caching, also referred to as client-side caching, instead stores this data at the client level itself. You see this daily when you visit sites — cookies are stored on your browser, caching certain data locally so that when you make future requests, that data is readily available. The same principle applies here, where data is cached locally to the requester.

Another option, edge caching, brings that content or system closer to the user, often geographically proximal to where their request might be generated. For instance, a user in San Francisco will have a request generated in San Francisco, and as such, it makes more sense to serve large content from a server located in San Diego than it would to serve that content from the service origination in London, England.

The problem with edge caching, of course, is that this is now largely a benefit for the user — the service provider now has to route that content service, spend more money on storage, and lose a bit of control if the processing for access to the service or content happens outside of the central processing servers.

Example Implementations

With this in mind, let’s take a look at some example use cases where hybrid and edge caching has been beneficial.

PlayStation Asset Streaming for Edge Gaming

A great example of a complex hybrid system can be found in a patent, US 2026/0034441 A1, submitted by Sony to the USPTO. In the patent, Sony describes a hybrid method for resolving some core problems with modern gaming systems, notably:

  • Asset libraries are growing larger.
  • Demands for affordability and reasonable console sizing are increasing.
  • Experiences requiring low latency and high resolution are generating conflict.

In this patent, dynamic asset requests are used to create a hybrid asset storage system in which geographically distributed resource caching stores commonly requested asset bundles — such as textures, meshes, and shaders — while core lower-resolution assets are stored at the local level. As the gamer uses the product, the client will request a higher-quality asset from the nearby edge, upgrading when needed and then downgrading when not needed.

This ultimately results in a system in which the remote server controls code execution and authentication, the edge cache serves higher-quality content via dynamic asset requests (LOD-based streaming) on-demand, and local caching serves the core product which drives higher-resolution requests.

For the end user, this means more affordable and lightweight devices that can still serve high-resolution content, which is vitally important for VR. For the provider, this means strong asset and auth control without having to worsen the product experience.

Netflix CDN Delivery

A classic edge caching story, Netflix uses edge caching to a great extent to power the delivery of its content at scale to its wide user base. Because Netflix has an international user base, its data provision is actually quite complex. Some titles are geographically locked, while others are universal — and throughout all of this, auth flows need to be centrally managed by regional control centers.

As an example, imagine two users — one in Japan, and one in the United States. In the US, certain animation titles are accessible by Netflix users — but even then, the content is regionally provided by edge servers in geographic clusters representing the East and West Coast and other subdivisions. A California user can retrieve content from the West Coast servers, and a user in New York will be defaulting to the East Coast servers.

Outside of the US, however, this content can be geographically locked — and in this case, both the content delivery as well as some of the auth flow and validation needs to be done regionally. The Japan user may not be able to access content that is licensed only for US release, as much of anime is, with the distributors providing alternative applications for that purpose.

For this reason, a hybrid approach is desired — data provision at the edge, authorization at the regional edge, and user validation at a central system.

Industrial Processing

Another common edge caching solution is in industrial processing. Systems that process APIs for states — such as reading from a Programmable Logic Computer (PLC) to publish the status of a button or commands to a stacklight — can store much of this data locally. The second you need that data to be used for more complex functions, however, you run into limitations of the machines themselves. PLCs generally aren’t supercomputers — or even regular desktops. They’re typically low power, low memory, low bandwidth, fanless, and driven by electrical signals rather than digital ones.

If you need to generate an inference model, then, your best option is to instead cache much of the data at the edge for processing elsewhere. By moving your data around using these APIs and storing at the edge, you can then cache the state of the data for local action while reading that data for external modeling and actions which can be sent back to the device.

This is especially important in low-connectivity environments. Consider a steel plant — heavily ferromagnetic systems can interfere with network connections, resulting in system that port data poorly and, even if they had the bandwidth to support it, would be a poor place for processing and creating models or complex actions.

By caching the state in a readable local signal and then porting that state for external processing, you can easily do more than you could locally without sidestepping the local data utility.

Choosing the Right Caching Layer

When trying to discover your best caching layer option, we do have to caveat any advice by saying that your build must dictate your caching choice. Every system is going to be slightly different, and as such, there’s no hard and fast one-size-fits-all chart to reference. That being said, there’s a few common generalizations that we can make which should help you choose your best implementation.

First of all, you should use edge caching when content is large, geographically distributable, and doesn’t require any per-request server-side logic. In these cases, notably seen in example deployments by Netflix and PlayStation, there’s no real reason to not cache at the edge — and failing to do so makes the user experience worse and your hard costs higher. In such a case, edge caching is really the most sensible choice.

When that logic shifts is when the server is involved. Security-sensitive, state-dependent, or server-logic-driven content cannot be served exclusively by the edge — and in many cases, caching anything at the edge is a significant risk. There are hybrid ways of managing this which we will get to shortly — but in such cases, managing at the server cache layer is best.

Client-side is an interesting middle ground, as it can serve user-specific, low-volatility cached content, and can tolerate staleness quite readily. For these purposes, they often find use in hybridized environments where the server logic must be processed against cached resources before regionally cached content can be accessed. In some cases, you can even store data client-side — but encrypted — pending server logic from the server side.

When to Use Both

With the complexity of caching solutions on offer, there is one option that many providers have adopted to try and get the benefits of both while reducing the drawbacks of either — hybridization. The core idea is simple — separate out specific domains of service and control, allowing you to retain control where it matters and gain benefit where it doesn’t.

Consider for a moment a service provider who is providing historical database access for weather information. This data can be quite heavy — and because of this, in order to control data bandwidth while also ensuring adequate access, authorization and authentication is used to control initial queries.

In a hybrid approach, you would break this process down into two core domains — the control system and the service system.

In theory, the database of historical data does not necessarily need to be accessible in its entirety at every single level and to every single user. The likelihood that a user in Sweden is researching historical data on our imagined API for weather in Djibouti is quite low — and conversely, there is minimal chance that the user in Djibouti cares much about the weather in Ontario. In this case, we can cache this commonly requested data by proximity — regional data mapped to regional provision, updated with out-of-region data in cache when one-off requests result in non-typical data provision.

This edge caching provides great flexibility and efficiency in data routing, but it’s still controlled by authentication — and in this case, we must ask ourselves if we really need to cache that process directly next to the user. To control the flow of data, we might cache some functionality like login page web assets or regional website variations, but the flow itself could still ultimately live in the remote server cache. Because the process of auth control is relatively lightweight, we can keep this close to the server while still ensuring the content is close to those who request it.

While this doesn’t negate the negatives of either — you still need edge caching servers and systems and you still have delays in auth for users — it mitigates them with better service provision, user experience, and control, giving you a sum of benefits that outweighs the sum of the negatives.

Semantic Caching

Semantic caching is an evolving solution designed to meet the needs of the modern connected API ecosystem. While semantic caching has been around for some time, it has seen rapid evolution and implementation as an LLM-centric caching approach. In this modality, semantic caching differs significantly from traditional cache-key matching, instead using similarity of request to cache to detect potential data service — and in the inverse, using semantic systems to determine what is the most appropriate element to cache.

Traditional caching was very much a sort of dictionary approach — knowing you’ll need to define something later, you simply write it down and reference it moving forward. But what if instead of looking up “bird” you were looking up “parrot?” Semantic caching allows you a bit of fuzziness, which is extremely useful for the highly probabilistic systems inherent to LLMs and AI API use.

Why Hybrid Approaches Are the Future of Edge Caching

Edge caching is a great solution to this problem, and it’s constantly evolving. Solutions abound for how to more efficiently control the flow of data and API calls, and while it’s not a solved problem, it at last has solutions which are relatively mature in 2026. Moving forward, much of our potential improvement will likely come from hybrid approaches — especially as APIs pivot from serving raw data into serving inference, measures, streaming content, and much more that is larger, more complex, and harder to compress.

AI Summary

This article explains when API providers should cache API calls at the edge rather than on the server or client, drawing on examples from gaming, video streaming, and industrial systems.

  • Server-side caching gives providers more control and security, client-side caching stores data locally to the requester, and edge caching places content geographically closer to users to reduce latency.
  • Edge caching fits content that is large, geographically distributable, and free of per-request server-side logic, while security-sensitive, state-dependent, or server-logic-driven content belongs in the server cache layer.
  • A Sony PlayStation patent and Netflix’s CDN delivery illustrate hybrid models in which content is served from the edge while authentication and authorization remain regional or central.
  • In industrial settings, edge caching lets low-power devices such as PLCs keep state locally while sending data elsewhere for modeling and complex processing.
  • Semantic caching matches requests by similarity rather than exact cache keys, making it well suited to probabilistic LLM and AI API traffic.

Intended for API providers, API architects, and platform engineers deciding where to place caching layers in distributed systems.