Citrix's Application Delivery Controller NetScaler is enabling organisations to take the first steps towards Software-Defined Networking (SDN), according to Citrix CEO Mark Templeton.

Speaking at the Citrix Synergy conference in Los Angeles, Templeton said that NetScaler is the company's fastest-growing product, because it delivers a mobile experience for some of the world's largest websites and enterprises, such as Amazon and Betfair.

It also runs at “cloud scale”, delivering over 1.4TB of throughput in one cluster, allowing customers to consolidate delivery services on a single platform.

In particular, the Netscaler SDX platform has been “growing like mad” because it enables enterprises to move to a more consolidated and converged infrastructure, providing application-defined controls and automatically applying policies on the physical parts of the network.

“When I think of this product, this is the SD in SDN,” said Templeton. 

Graham Melville, director of product marketing for Citrix cloud networking, explained that NetScaler works a bit like a telephone operator, inspecting packets as they come over the network and sending them to the right server.

It also makes servers more efficient through load balancing, and includes a wide range of security features for blocking malware and distributed denial of service (DDOS) attacks.

“People think of us as a network appliance, but we actually work at much higher levels of the network. So Cisco and Juniper do the Layer 2 and Layer 3 stuff, whereas we're right up at Layer 7, looking into the actual applications,” said Melville.

“That's where things like the app firewall are. Network firewalls aren't going to stop anything, because it's HTTPS traffic so everything's going to come through - good or bad. That's why you need to go higher up in the application layer and look to see more deeply what's going on.”

NetScaler is central to Citrix's new Worx Mobile Apps offering, which allows any application to connect to backend infrastructure securely via a micro VPN. Melville said that NetScaler enforces the security, and the micro VPN is used on a per-application basis to secure the traffic.

Citrix recently added a new feature called HDX Insight, which gives IT departments in-depth visibility into all the traffic that passes through NetScaler. This makes it easier for users to troubleshoot application performance problems in complex network and data centre environments

Of course, administrators have long had command-line tools, such as ping and traceroute, to diagnose network problems. HDX Insight was designed for administrators unfamiliar with such tools, especially those with more experience supporting applications than networks.

"This allows the help desk guy, who doesn't know anything about networking, to be able to know if a problem is a network issue or an application issue," Melville said.