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Network Computing teamed with Cisco Systems and Microsoft Corp. to perform some hands-on testing of next-generation IP-multicast applications. Using available hardware and software, we demonstrated the capability to bring high-quality full-motion video and audio to the desktop. Microsoft has taken this technology one step further by deploying a multicampus production IP-multicast network. We had the exclusive opportunity to tour the heart of its infrastructure and see up close how multicast works. In this workshop, we'll look at the architecture and find out how IP multicast can save money, increase productivity and provide useful end-user services.

Breaking Down the Walls IP multicast has been around for more than 10 years, but for the most part, the multicast address space is just another mysterious range of IP addresses ignored by network administrators. Taking advantage of this functionality has been hampered by lack of software support. Furthermore, bringing audio and video to the user's desktop has been considered an expensive and complicated upgrade process. Our testing shatters those myths, and we conclude that IP multicast is ready to be ushered into enterprise intranets.

When we arrived at the Microsoft campus, we were thoroughly convinced that IP multicast was a high-end application for only the most elite PCs. But after three days of testing in Microsoft's NT Performance Lab, we changed our tune completely. IP multicast can be successfully deployed in typical enterprise environments.

The elite hardware anticipated was nonexistent; we tested IP multicast on 72 100-MHz Pentium clients, far from the supermachines we expected for this test. The resulting full-motion video and real-time audio came through crystal clear on the test clients. And network load was less than 10 percent. Quite simply, we were impressed with its performance.

Using Today's Resources For many sites, the lack of hardware and software has prevented IP-multicast technology from being deployed. Network hardware vendors haven't let a lack of applications slow their multicast development, however. A quick check of a typical intranet infrastructure reveals that most of today's switches and routers are ready to manage IP multicast out of the box.

To deliver IP multicast traffic to the desktop efficiently, a solid-switched infrastructure is a necessity. If your organization has been hemming and hawing over switched 10-Mbps networks versus shared 100-Mbps networks, here's the perfect reason to deploy switched 10. Switches that provide intelligent multicast control via IGMP (Internet Group Message Protocol) snooping will help keep network traffic to a minimum, while still providing ample bandwidth to all users.

A desktop computing platform typically comes with at least a 100-MHz processor, integrated sound card, CD-ROM and a 10-Mbps network interface card. Advanced compression algorithms and encoding techniques enable this hardware to play back high-quality audio and video streams using minimal bandwidth. And the hardware required to achieve these services is present in the client. The ability to deploy IP multicast without serious desktop changes may change your tune on multicast technologies.