Much of the discussion about software-defined networks focuses on the network side of the story. But vendors are revealing plans that will allow applications and services to take advantage of the programmability promised by SDN. Citrix Systems has announced a forthcoming version of its NetScaler SDX application delivery controller that aims to do just that.
The company says its next-generation NetScaler SDX will interoperate with commercial SDN controllers via the controllers' APIs. This will enable customers to provision new services and applications from NetScaler, which will in turn leverage the controller to automatically provision the appropriate network configurations. However, the company says the new version of NetScaler won't be available until early 2013. The company also declined to specify which controllers it would work with.
Customers need not learn any scripting or programming language to provision and deploy applications, Citrix says. Instead, the company provides AppTemplates for popular applications that can be downloaded, imported and customized. When a new application is ready to go live, administrators can select the network services the application needs via the NetScaler SDX, including load balancing and firewalling.
Other capabilities of the forthcoming NetScaler SDX include AppFabric, which provides a common underlying multitenant framework for third-party services to plug into the platform, and AppFormations, which helps simplify deployment of applications by prepackaging the network services and topology needed for common use cases.
Citrix sees application awareness a critical part of the overall SDN promise of flexibility, as SDN is primarily focused on Layers 2 and 3, even though enterprise applications are driving network requirements. As Network Computing editor Mike Fratto recently blogged, application network service insertion is a critical gap that needs to be closed so enterprises can automate the entire application deployment process. He said application mobility and dynamic scaling mean using an application model where the networking requirements are defined as part of the application profile and can be applied anywhere, with any underlying hardware. Fratto also wrote that "a top-down approach in which the application tells the network what it needs will be the norm."
Applications are the reason for the data center, says Bob Laliberte, a senior analyst at Enterprise Strategy Group. "The goal of these new application architectures is to accelerate creation and deployment. The network can't be the bottleneck to application deployments."
Laliberte says the most common network challenges stem from too many manual processes and from delays in provisioning or reconfiguration of network devices. "The ability to automate these processes will be important, especially as more organizations consolidate data centers and the network rapidly scales and grows more complex." Citrix is opening up NetScaler SDX to partners, including Aruba Networks, Palo Alto Networks, RSA, Trend Micro, and Websense, to enable their network services to work with the platform. The company specifically called out its partnership with Palo Alto as a partner for implementing application control and firewall services within the upcoming NetScaler SDX platform.
Citrix isn't the only vendor moving in this direction. Rohit Mehra, director of enterprise communications infrastructure at IDC, says F5 Networks has taken a similar approach to connect to partners that help solve complementary problems. F5 recently announced that its BIG-IP application delivery product suite will be integrated with VMware's vCloud product suite. Meanwhile, this week Hewlett-Packard announced that it plans to release applications that were designed to leverage an SDN controller, but the company said they wouldn't be generally available until next year.
Citrix says the forthcoming version of NetScaler SDX will be available as a physical appliance with multitenancy support, and it will be aimed at both enterprises and cloud service providers. Citrix did not announce availability or pricing for NetScaler SDX but says customers will be able to incorporate it into their network architectures in early 2013.