What is an Application Delivery Controller (ADC)?
Just when you think you have a good handle on the key technologies on the market, they come up with something new. If you’ve been told that you need to look at putting in an application delivery controller (ADC), read on.
What is an Application Delivery Controller?
Application Delivery Controllers (ADC) provide security and access to applications at peak times. As computing moves to the cloud, software ADCs perform tasks that have been traditionally performed by custom-built hardware. They also come with added functionality and flexibility for application deployment. They let an organization quickly and securely scale up its application services based on demand in the cloud. Modern software ADCs allow organizations to consolidate network-based services. Critical capabilities for application delivery controllers include SSL/TLS offload, caching, compression, intrusion detection, web application firewalls, and microservices for container applications. This creates even faster delivery times and greater scalability.
How does it work?
An Application Delivery Controller essentially functions as a load balancer, optimizing end-user performance, reliability, data center resource use, and security for enterprise applications. But ADCs also perform other functions, like application acceleration, caching, compression, traffic shaping, content switching, multiplexing, and application security.
An ADC accelerates the performance of applications delivered over the wide-area network (WAN) by implementing optimization techniques, such as application classification, compression, and reverse caching. Typically, ADCs are placed behind a firewall and in front of one or more application servers to act as a single point of control that can determine the security needs of an application and provide simplified authentication, authorization, and accounting.
Application Delivery Controller Features
An application delivery controller can come in different forms factors. It can exist as a dedicated piece of equipment. An ADC can be a virtual device on the cloud. Or it can come as a software-only solution.
The list of features will vary from vendor to vendor. Here are some of them:
- Automatic application health checks
- Proxy and reverse proxy
- SSL Offload
- Caching
- Data compression
- TCP multiplexing
- Traffic shaping
- Web application firewall
- DNS firewall
- DDoS protection
- AAA server
Notice that many of these features can be viewed as belonging to the function categories already discussed: load balancing, application acceleration, and security. It should be clear by now that an ADC does a whole lot more than just load balancing.
Why do organizations use Application Delivery Controller?
Applications have evolved significantly over the years. The term “delivery” is now generally accepted as the means of bringing an application to the user in the era of mobility and cloud. In the enterprise, business applications have moved away from desktop-bound software installed on a local server accessed by users across the LAN. Modern applications need to work across all types of networks and at locations beyond the confines of the physical workplace.
Application delivery controller, which is widely deployed as a key fixture in the enterprise, helps applications adapt to the networks and protocols that are in place today. They also ensure that applications perform optimally, are always available, and don’t present any security risks either to the user or business.
This is especially important given the needs of an increasingly hybrid workforce.
The average consumer expects the devices and applications they interact with daily to always work, and for information to be instantly available on demand. These expectations have carried over to the types of devices and applications they use. To satisfy today’s workers, business applications need to be as intuitive and easy to use as the ones they rely on for personal tasks and entertainment.
Many employees are no longer restricted to using locked-down, company-owned equipment, and can use personal devices to work whenever they choose. With people working at any time of the day or night, IT must be certain workplace servers and applications are available around the clock. Enterprises invest heavily in IT infrastructure to ensure that employees always have access to applications and information when they’re needed.
Of course, servers can fail for several reasons ranging from mechanical problems to over-utilization and security breaches. If a server goes down, applications running on it become unusable or inaccessible.
IT organizations can plan for these occurrences by building fault tolerance in their environments. Deploying additional servers in the data center or at a co-located site are typical failover strategies. ADCs can help ensure the high availability of applications by providing seamless failover. This is done by balancing application workloads across a cluster of active servers in one or multiple sites.
What’s next for ADCs?
Application Delivery Controller already provides tremendous value to IT organizations ensuring the secure delivery of applications and data to the user. However, they are expected to continue advancing as applications evolve. Software-defined networking (SDN) has placed increased demands on application delivery controllers to function “as a service.” As network protocols become more application-centric, ADCs must also adapt and become more “self-automated” to provide seamless optimization and protection for every type of application.
Conclusion
An application delivery controller offers a single point of control. Using a single device for so many capabilities means that we keep learning how to do more with less. The ADC is an important addition to modern networks. Have you installed yours yet?