In the 19th century, carts and carriages were drawn by horses. These animals had to be taken care of — fed, groomed, and sheltered — in addition to the maintenance of the vehicle they were moving. The arrival of the automobile made overland travel not only much faster, more reliable, and more convenient, it also revolutionized the architecture of the moving force: The horses, or rather their horsepower, morphed from an external entity into an integral part of vehicle design.
A similar revolution is happening now in application development and application delivery optimization. The application delivery controller (ADC) used to be a separate — originally physical, later also virtual — network component, managed by the network team and deployed in front of a server farm to optimize application performance and security. DevOps and agile development have fundamentally changed this situation: The ADC has turned into a critical building block of the application itself.
Instead of creating, or updating, applications in the quarterly or even annual cycles of traditional “waterfall” app development, agile development methods have cut the cycles down to the few weeks of a development sprint. At the same time, DevOps — by merging application development and operations — has reduced deployment times, ultimately leading to continuous integration and continuous delivery (CI/CD).
This dramatic acceleration means that the distinction between app development and app deployment has all but disappeared — it is no longer a separate activity to deploy and configure ADC appliances after app deployment for much-needed performance optimization, high availability, security, and resilience for the application. Rather, with developers making almost instantaneous changes to their apps, they need to take care of performance, high availability, security, and resilience issues themselves. In security circles, one aspect of this transformation is known as “shift left security.” Development teams must now take responsibility for the security of an app. So the security must be embedded by design, instead of leaving the task to separate application firewalls and other security solutions.
ADCs: Not Just a Piece of Hardware Anymore
The same principle applies to all the optimizations an ADC provides. The ADC isn’t simply a piece of hardware anymore that the network team harnesses to speed up applications and make them more reliable. Rather, the ADC is now part of the CI/CD pipeline — it’s becoming a piece of the application infrastructure instead of a separate appliance in a data center rack.
A modern-day ADC must integrate natively into deployment and orchestration tools such as Kubernetes, support continuous deployment using tools like Spinnaker and Kayenta, and connect easily into event monitoring software like Prometheus and Grafana, while being flexible enough to be quickly and easily integrated with other tools at pace with minimal effort. Only an extensive level of integration gives developers the visibility and optimization toolset needed to make sure that the applications they design are well-performing, highly available, and secure.
Some DevOps teams prefer using open-source tools for these tasks. While this approach has its merits, market-leading commercial ADC solutions such as Citrix ADC bring a critical advantage to the app development race. This allows developers to focus on the delivery of new features and capabilities, to improve customer experience by offloading the burden of integration and maintenance into common toolchains in a highly secure and performant solution using extensive reporting tools. These take away management overhead, by providing pre-built solutions based around popular third-party solutions and offering a full set of APIs and templated environments to reduce the toil associated with keeping this necessary infrastructure “fed and watered.”
They also provide helpful pre-defined services in the form of custom resource definitions (CRDs). These CRDs help to simplify the rollout of commonly used scenarios and can help DevOps teams get new applications to customers faster and more securely, for example, ingress proxy services for Kubernetes, allowing each micro-service to quickly get its own proxy and support rich Layer 7 policies to manage security and enhance application performance.
Powering Modern Applications
To summarize, ADCs have evolved from hardware appliances installed in a rack and managed by the network team to software that not only handles external traffic distribution, but also communications between the many and varied components of a modern app and is integrated into its continuous deployment lifecycle, adding multiple layers of add-on value to agile application development. In our incredibly fast-paced digital business world, a comprehensive, API-rich ingress solution such as Citrix ADC allows companies to not only move fast, but to create the performance-optimized, highly available, and tightly secured applications that really drive business value. ADCs provide the integrated horsepower for modern applications.
Learn more about how Citrix ADC can help you deliver a high-quality user experience for your web, traditional, and cloud-native applications regardless of where they are hosted.
