Job Corps trains young people from ages 16 to 24 with courses such as auto repair, building maintenance, data entry and nursing assistance. The organization runs Cisco's IP/TV clients on 7,000 PCs nationwide for videoconferencing and streaming video of its presentations, training and administrative videoconferences. It's all about making training more accessible, and the combination of multicasting and streaming video gives Job Corps flexibility in distance-learning courses. If a student misses an automotive training session that's streamed over the network to the IP/TV servers, for instance, he or she can view it at another time from one of the IP/TV workstations.

"We can have an instructor in front of a video camera in one location while Job Corps students in classrooms or desktops elsewhere receive the multicasted video," Vazquez says. It's cost-effective, too, he says, since there's no difference in the amount of bandwidth used in multicasts to one or to 1,000 users.

The key is making sure the video -- and voice -- isn't jerky or delayed. Job Corps doesn't take any chances and protects itself with QoS (Quality of Service), even on the LAN. Vazquez argues that massive LAN bandwidth isn't enough for IP voice and video. "If you're going to think about doing IP voice and video, you have to have QoS on the LAN," Vazquez says. "The more videoconferencing you do, it is only a question of time before congestion becomes an issue."

Delay can occur when a LAN is traditionally configured with a single queue for all packet types. Even a Gigabit Ethernet pipe will resort to first-in, first-out queuing, which means voice traffic can get pushed aside by other packets, Vazquez says. To remedy that, Job Corps is configuring its Cisco routers and switches to provide a separate LAN queue for voice and video so they don't have to compete with data traffic for LAN bandwidth. Vazquez says Job Corps doesn't use RSVP (Resource Reservation Protocol) in the Cisco gear for reserving pipe for video, however, because RSVP doesn't recognize multicast calls.

Job Corps also uses the QoS functions of ATM on its WAN as well, with three virtual paths, one for voice and video at 256-Kbps sustained cell rate, and two 65-Kbps connections for its SQL and other traffic.

In addition to the new video traffic, Job Corps is extending VoIP (voice over IP) across its WAN; it already has VoIP in its LANs. One of its hurdles in setting up voice and video over its WAN has been configuring dial plans for voice and video clients. That requires setting up not only the physical end point of a call but also the features and bandwidth associated with the H.323 voice and video gateways. "The IP/voice and video technology works," Vazquez says. "But setting dial plans in such a manner where you don't have to go back and reconfigure how you name clients is [challenging]."