Application delivery controllers can be deployed in a variety of use cases, but an underestimated one is the ADC security use case. When it comes to data center security, ADCs are used to protect websites, hide server IP addresses and buffer distributed denial of service, or DDoS, attacks. According to Doyle Research, the ADC security market exceeds $1 billion and continues to grow, evidence that the ADC security use case has gained significant traction.
Role of the ADC
ADCs are deployed physically or virtually — either as a hardware appliance or software instance — and sit between the firewall and application servers. They manage the flow of data between users and server-based applications. ADCs use a number of techniques to optimize application performance — among them, traffic identification, data compression and reverse caching.
Security threats to the data center
IT systems are particularly vulnerable to online attacks as companies conduct business, use cloud-based resources and support a remote, mobile workforce. Hackers and cybercriminals constantly attack websites and data centers in organizations of all sizes. The result of these attacks can lead to downtime, application slowdowns, data loss and ransomware — all of which can reduce customer satisfaction, decrease revenues and threaten intellectual property.
Intrusions come in many forms. Internet connections can be exploited to discover the identity of web-facing servers. Users can be infected with malware and thus disclose username and password information. Attackers use Secure Sockets Layer encryption to hide their activities from internal security systems. Infiltrators can also launch DDoS attacks to take down critical websites. Other potential threats include SQL injection, cross-site scripting (XSS) and man-in-the-middle attacks.
Evolving data center security requirements
Using software-defined technologies as their foundation, IT organizations today deploy a variety of flexible private cloud resources in their data centers. Software-defined data center networks tap into a variety of adaptable compute and storage resources to deliver a specified level of performance for critical applications.
Network security resources must respond dynamically, reallocate as needed to address changing application requirements, support changing traffic patterns — like east-west traffic — and manage shifts in network traffic. The transformation of the data center makes for a substantial ADC security use case.
ADCs in data center security
ADCs can be considered an integral part of data center security, along with next-generation firewalls, intrusion detection systems, VPNs and other security components. More specifically, ADCs are used in three key areas when it comes to a security use case:
- Web application firewalls. ADCs can be deployed as a WAF, protecting websites against application layer attacks, SQL injection, XSS and zero-day threats. WAF provides security without degrading network throughput or application response times.
- Network address translation. Using NAT, ADCs can prevent hackers from obtaining IP addresses of network content servers. NAT masks the real IP address of the server, thus protecting it from potential attacks that could expose security vulnerabilities.
- DDoS. DDoS attacks bombard servers with so much traffic and from so many sources that they can no longer function correctly. ADCs can function as shock absorbers by identifying anomalous traffic patterns and blocking access to the targeted server. They can also impose bandwidth and rate limits on traffic, as well as identify bot-generated traffic.