Cisco goes with ContentFlow

With the spread of e-commerce, Web hosting and Web-based applications, ISPs are advancing rapidly beyond straight connectivity to content delivery. And that means taking a different view of their infrastructure, according to an announcement expected to be made this week by Cisco Systems.

As the underpinning of this content-based network, Cisco will unveil its ContentFlow architecture, a technology initiative that it claims will result in networks designed not just to forward packets but also to manage the efficient creation and termination of content flows.

"Connectivity was about reaching a destination, and it was static," said Susan Scheer, director of services and solutions marketing for Cisco's service provider division. "Now it's dynamic, and it's about accessing content. The network itself needs to be aware of the content, and for that, you need to lay the proper foundation."

The difference is end-to-end responsibility. A forwarding network delivers a packet to a server or client but doesn't concern itself with the status of the destination. But if the end user cannot access the content, the network has failed to live up to its responsibility, said Cecil Christie, manager of service marketing for Cisco's Web hosting solutions product group. "Our goal is first to develop a network that participates in the content distribution and then optimizes itself for efficient content access," he said.

Therefore, a content network needs continuous feedback among its elements. ContentFlow Architecture builds this into network Layers 2 and 3 with flow management agents and flow delivery agents. Flow management agents will reside within Cisco's routers, switches, cache engines and content appliances, such as its Local Director and Distributed Director servers. When a content request comes in, flow management agents will "talk" among themselves using Web caching control protocol and dynamic feedback protocol and determine the best route to get that content to the end user.

Once endpoints are established, flow delivery agents will deliver the packets inside a flow as efficiently as possible, using policies to set quality of service (QOS) standards while also performing housekeeping tasks for packet flows.

Elements of the ContentFlow are out already on the Internet, and some long-time Cisco service provider partners are preparing to test new developments as they come down the pipe.

Web hosting company Digex sees benefits in the development of differentiated services. Financial sites usually involve free areas, members-only areas and perhaps a higher priced real-time stock quote area, said Charles Boyle, director of research and development for Digex. With ContentFlow, these areas can be hosted on the same server with greater QOS granularity.

"The free area could get best-effort IP, the member area could get a certain amount of bandwidth not to exceed x and the real-time feed would get a much higher priority because you don't want to drop streaming packets," he said.

In early October, the NetAid Web site that Cisco has assembled in partnership with Akamai Technologies and Real Networks will host live concerts and serve as a proof point of the ContentFlow concept.

"We've taken it upon ourselves to create a very big distributed Web site, global in scope and highly scalable," Christie said. "We'll distribute the NetAid content efficiently and update it in real time. It will represent our thinking about how to create a large Web site."