Authorization at the edge

Slow authorization in systems can lead to user frustration, resulting in lost productivity and declining user conversions. Imagine a user trying to view a document on a workspace application and encountering an authorization lag where they must wait for several seconds. This delay disrupts their workflow, making them wonder whether they have the correct permissions or if the system is malfunctioning.

These moments of friction highlight that authorization is not merely a technical security measure but an important aspect of user experience (UX). How an application handles authorization directly impacts a user’s trust in the system, their perception of its reliability, and ultimately, their willingness to continue using it.

Authorization as a UX concern

Delays in authorization processes like logging into an account, granting permissions, or completing security checks, affect user engagement. Users expect seamless interactions, and prolonged waits can lead to frustration, task abandonment, and reduced trust in the platform.

Poor authorization UX, which results in longer wait times, can lead to consequences for business and productivity. For example, users may abandon their shopping carts if the flow from add-to-cart to checkout encounters a lag in checking if they are qualified for a discount.

Another consequence can be seen in work environments where employees try to access a document, and the authorization process lags. This can lead them to question whether they have the proper permissions, thus disrupting their workflow.

The overall consequence of bad authorization UX would be brand damage and loss of users. If users associate your product with bad authorization UX, they may consider alternatives with better UX. To address the poor authorization UX caused by latency, let's explore edge authorization as a solution.

Understanding edge authorization

Traditionally, when a user makes a request to an application, the request may have to travel a long distance, perhaps halfway across the world, to the centralized servers that process it.

The time taken to complete these requests varies depending on the user’s distance from the centralized servers. This introduces some latency for users located farther from the central server.

Edge networks and CDNs improve the latency associated with these round-trips by processing data and delivering services closer to the user using a network of geographically distributed edge servers. With edge networks, the user’s request travels to the nearest edge server for processing.

Similarly, in traditional authorization, when a user makes a request to a protected endpoint, the client sends the user’s data to the centralized server, which checks if the user has the required permissions and allows/rejects the request based on the user’s access levels. This approach is prone to a few problems, such as increased latency in processing requests and difficulty scaling as users grow.

Edge authorization solves these issues by moving decision-making closer to the user . It leverages edge servers instead of a centralized server to enforce access policies and execute authorization logic.

This approach ensures faster response times, reduces latency, and enhances security by keeping sensitive data and logic near its source. Let’s explore the benefits of edge authorizaton in detail.

Advantages of edge authorization

Edge authorization offers several benefits over traditional authorization implementations, sin the areas of latency, reliability, and scalability.

Reduced latency

Since the authorization process occurs closer to the user, minimizing the round-trip time to the origin server. This reduces the time required for authorization and content delivery.

This faster authorization translates into faster page loads and API responses, which significantly improves user satisfaction. In industries like e-commerce and gaming, where slight delays can lead to lost customers, it provides a competitive edge.

Reliability improvements

Edge authorization can be more reliable than traditional authorization in some cases. For example, if one edge server experiences downtime, requests are routed to the nearest available server without returning to the central origin. This failover mechanism ensures quick response times even during outages.

Authorization on edge also creates multiple pathways through which authorization requests travel to ensure continuity even if one route fails. Additionally, it balances the traffic across multiple edge servers to prevent the overloading of a single server.

Performance and cost improvements

Traditionally, a single central server often handles most operations, making the system vulnerable to performance bottlenecks during periods of high traffic or unexpected surges in user activity. This affects multiple processes including authorization.

However, in systems implementing authorization on the edge, authorization processes are relatively unaffected during unexpected surges in user activity as authorization tasks are spread across the edge network, reducing the burden on central servers during peak traffic.

Additionally, offloading authorization to the edge decreases both the computational and bandwidth demand on the origin servers, thus reducing overall server costs.

Implementation challenges and solutions

While edge authorization offers many benefits, implementing it properly can be complex. Here are some common implementation challenges associated with edge authorization, and solutions you can implement to solve them.

Synchronization challenges

Edge servers operate independently to distribute workloads, be fault-tolerant, and reduce latency. However, this distributed model can lead to delays or inconsistencies in the propagation of authorization rules. In this case, some edge servers would have the latest rule changes, and others would not.

To ensure real-time updates to authorization policies across all edge nodes, you can use a centralized configuration management system like Cerbos Hub or AWS AppConfig to manage and deploy policy updates simultaneously across all your edge servers. Additionally, you should implement version control for authorization rules, allowing rapid rollback if inconsistencies occur.

Maintenance challenges

Due to the distributed nature of edge servers, it can be difficult to aggregate logs or monitor performance in real-time. This also makes debugging very difficult as it can be hard to pinpoint the root cause of a failure that occurs across multiple edge servers.

To make your edge authorization solution easier to maintain, you can consider using centralized tools like Cerbos Hub or Datadog to aggregate and analyze logs and stack traces from your edge servers.

Security implications

Edge servers rely heavily on cached data to reduce latency. However, this introduces security challenges when you implement authorization on edge. For example, outdated user permissions might grant or deny access inappropriately due to failure to invalidate caches properly.

Additionally, due to the distributed and publicly accesible nature of edge servers, authorization logic is exposed to a broader range of attack vectors (e.g., replay, token interception).

To address these security vulnerabilities associated with edge authorization, you should implement short cache lifetimes to reduce the risk of stale information and deploy WAF (Web Application Firewalls) in front of edge servers to filter malicious traffic before it reaches your edge servers.

Real-world examples

Let’s explore some real-world scenarios where edge authorization can improve the overall authorization UX of your application.

Festival scenario: Limited bandwidth, high concurrency environment

Edge authorization can be advantageous in scenarios with limited bandwidth and high concurrency. Consider, for example, a large-scale music festival with multiple entry gates and thousands of attendees.

The high user density would cause long slow queues and angry concert-goers due to the consumption of the available network bandwidth and the high-volume ticket scanning at multiple entry points to verify attendee tickets, as a centralized server may not be able to handle the load.

However, with authorization implemented on the edge, you can achieve high-speed ticket validation without needing a round-trip to a central server. Dependency on the network is also reduced due to the cached data ensuring smooth operations in low-bandwidth conditions.

Global access patterns: Multinational software organizations

Software organizations with globally distributed teams require consistent API response times across all teams to collaborate effectively. However, API response times can vary due to centralized Policy Decision Points (PDPs) located in a single region, and engineers in remote regions can experience delays, thus impacting productivity.

Consider, for example, an organization-wide meeting where some employees are experiencing delays joining the meeting due to an authorization lag caused by a centralized PDP. This would waste everyone's time while they wait for everyone to join and can be costly if the subject of the meeting is a critical issue, such as a security breach.

Using edge networking, you can deploy PDPs at edge locations close to each major region. Each PDP evaluates API access policies locally, reducing the latency experienced by the engineers. This would result in more uniform API response times globally, and improved developer experience and productivity for your organization.

Video streaming platforms: Global content delivery with regional licensing

Video streaming platforms usually serve a geographically distributed user base, and different content licensing agreements apply to different regions.

To ensure they don’t infringe on licensing agreements, they need to perform multiple geo-restriction checks to confirm a user’s regional permissions. Performing these checks on a centralized server can lead to buffering delays, ultimately affecting the user experience.

With edge authorization, you can embed geo-restriction logic at the CDN level, allowing edge servers to handle content access decisions without routing every request to a central server. Handling these geo-restriction checks with edge servers can ensure seamless playback with minimal buffering, while also enforcing regional content restrictions.

Healthcare operations: Multi-facility hospital network

Multi-facility hospital networks with geographically distributed branches need to access sensitive patient records with minimal delay, as delays in accessing records could compromise patient care. A centralized authorization system in scenarios like this would be subject to large traffic cause by manay concurrent requests to access, create, and update patient records. This traffic could slow down the process of retrieving and using patient information.

An authorization system on the edge however can distribute the load across edge servers and enable rapid permissions checks while maintaining regulatory compliance. Thus giving healthcare workers in the facility immediate access to critical patient data.

Conclusion

Bad authorization UX affects a user’s engagement with your application—especially bad UX caused by authorization latency. Authorization latency can be associated with bottlenecks created by centralized approaches, which you can solve by implementing authorization on the edge.

Successfully implementing edge authorization requires careful consideration of the deployment, maintenance, and security challenges associated with it. However, a successful implementation can be advantages in many industries like healthcare, entertainment, and productivity.

Keep the story going!

If you want to dive deeper into implementing and managing authorization, join one of our engineering demos or check out our in-depth documentation.