Video Delivery Products Enhance Distance Learning Quality
By Linda L. Briggs
Colleges and universities delivering distance learning via the Internet face challenges in maintaining high-speed, high-quality voice, video, and data. Delivering video and voice courses using Internet protocols (IP) has been growing over the past five or six years, and technology companies are racing to keep up.
Many of the challenges are highly technical ones involving the best standards for sending content from one location to another. Voice and video is condensed, or “coded,” on the send side, then decoded on the receiving end using codec equipment. The challenge is to have the decoded content appear as the sort of high-quality displays and sounds that users have become accustomed to.
As chief engineer of educational technology at the University of Virginia (UVA) in Charlottesville, VA, Bob Hutchison wrestles with those sorts of problems regularly. UVA delivers graduate engineering courses, among others, over IP. Content is delivered to community colleges, business sites, and higher education centers, not only across Virginia, but nationwide. The instruction is recorded on-site at the university. Receiving centers must be running some sort of codec system in order to receive and decode the content for display in class.
Last year, UVA began moving from ATM (Asynchronous Transfer Mode) technology to Internet protocols for its digital video conferencing, according to James Grove, assistant dean for research and outreach. Grove, who has been involved in distance learning for 20-plus years, said UVA was looking for new equipment, bridges, and codec systems for its multipoint course distribution system.
One of the challenges UVA faces, as with many schools delivering high-end distance learning content, is that each site may be using a different type of receiving and decoding system, ranging from legacy to the most current standards.
To get around that issue, UVA delivers class content using three products from Codian, a manufacturer of high performance video conferencing infrastructure. (Models in use at UVA are Codian MCU 4210, Codian ISDN Gateway 3240, and Codian IPBCR 2220.) The university selected the products partly because of their versatility in handling many different sites, with different standards at each port, at one time. “One thing we like about Codian,” Hutchison says, “is its great versatility in trans-coding the signal to each port. It can connect to each site regardless of what [standard] they’re running.”
That feature has helped make Codian the standard-bearer for high-speed video delivery over IP, Hutchison says. Codian products can connect to multiple codecs at different sites, with equipment of varying ages and from different manufacturers, and running at different video and audio speeds. “Codian treats each individual connection discretely,” Hutchison explains, “and will do the best that it can [at each site].”
Competing products offer that capability, Hutchison says, but at a significantly greater cost and not always as smoothly. A Codian 20-port bridge product can handle every single port at a different speed, if needed. “Other products are limited to the number of trans-codings you can do,” Hutchison says. That drives up the cost-per-port for other products.
One of the goals for UVA’s distance learning program, especially regarding faculty, Grove says, is a seamless system. “We want the distance teaching experience to be the same as the standard [face-to-face classroom experience]… Distance shouldn’t act as a barrier for faculty.” As digital video technology matures, that goal of seamless delivery is becoming easier.
Linda L. Briggs is a freelance writer based in San Diego, Calif.
