Networks have traditionally supported applications by providing a transport service. Over the years, this transport service was optimized through QoS mechanisms in an effort to prioritize one set of applications over another.

The type and number of applications have increased dramatically, driving new application-support requirements within networks. A new class of network service called Application Intelligence has emerged to address a series of problems and provide IT leaders with tools to optimize application performance while improving the user experience.

One example of Application Intelligence can be found in routers today via Cisco's NBAR or Network-Based Application Recognition. To expand NBAR's functionality reach throughout a corporate network and increase performance to the multigigabit level, Cisco introduced its Programmable Intelligent Services Accelerator, into the Supervisor Engine 32 for the Catalyst 6500 series of switches on April 30.

There are appliance-based Application Intelligence solutions as well, from such vendors as Packeteer, F5, BlueCoat and Riverbed.

Application Intelligence is being deployed at the network access and the demilitarized zone, creating an Intelligent Edge and Intelligent DMZ. The Intelligent Edge surrounds a network at the wiring-closet level, classifying applications, assigning priorities, defending against Day Zero exploits, and providing IT executives with application and network-behavior information.

The Intelligent DMZ provides protection for Web servers, while alerting operations of suspicious traffic flows. Application Intelligence provides insight into Internet traffic flows and policing of application types, eliminating unsupported applications before they traverse the Internet, optimizing bandwidth for mission-critical applications and appropriate use.

The Intelligent Edge and DMZ prioritize mission-critical applications, preserving IT investments and optimizing business processes.

Application Intelligence has become available at the right time, as new application-delivery models have emerged, representing unknown and unforeseen traffic patterns and network loads.

Structured IT applications are converging upon Web services, which make it difficult to distinguish mission-critical from recreational applications. With unstructured applications based on Enterprise 2.0 technologies -- such as RSS, AJAX, mashups, wikis and service-oriented architecture -- network behavior is unknown. Thin-client and back-end-based application delivery are other network unknowns.