Networking

Optimizing Video Conferencing

Try these five strategies for delivering high-quality video traffic.

Irwin Lazar is vice president and service director for Nemertes Research.

Just when you thought you solved Voice over IP quality challenges, along comes video. Like VoIP, video conferencing requires careful attention to latency, jitter and packet loss. But video adds a new wrinkle — demand for lots of bandwidth.

Fortunately, several strategies can help you deliver high-quality video while minimizing network costs.

Tip 1: Boost Bandwidth

Regardless of technology choice or type of endpoint, you'll need ample bandwidth to support video conferencing. High-definition desktop, room and immersive telepresence systems can eat up from 2 megabits per second to 6Mbps per endpoint.

With average branch bandwidth growing by more than 500 percent in 2011, the need to support video conferencing is a primary driver for adding bandwidth to branch locations. Most organizations have added anywhere from 1Mbps to 6Mbps per location to support video.

Tip 2: Plan for User-Generated Video

More than half of enterprises are deploying platforms to let users generate, stream and store their own video. Typically it starts with recording video conferencing sessions for later playback, but in the age of YouTube, an increasing number of organizations are giving employees the ability to use their camera-equipped endpoints to generate video for information sharing and collaboration. Evaluate strategies such as caching, content distribution and multicast distribution to reduce streaming video's bandwidth demand.

Tip 3: Re-evaluate Your WAN Architecture

Room and telepresence video are relatively easy to plan for; you can predict traffic flows and usage and design accordingly. Desktop video conferencing creates uncertainty because it's difficult to predict who needs to connect to whom, when and for how long.

The any-to-any nature of desktop video requires a re-evaluation of WAN design, away from hub-and-spoke models optimized for desktop-to-data-center traffic flows and toward any-to-any design models based on Multiprotocol Label Switching or Virtual Private LAN services.

Tip 4: Adopt Application Delivery Optimization

Application delivery optimization (ADO) goes beyond simple quality of service, enabling network managers to guarantee sufficient application performance in the distributed and mobile world. Effective delivery encompasses both application availability and performance management. ADO makes it possible to prioritize video traffic flows and compress and/or cache traffic to reduce bandwidth demand. As part of an ADO strategy, evaluate call admission control capabilities to ensure that you allow only the amount of video traffic that your LAN and WAN can support.

Tip 5: Evaluate Emerging Technologies

Explore some of the new emerging technologies to reduce bandwidth requirements or support high-definition video over less expensive networks such as the Internet. Examples include H.264 Scalable Video Coding (SVC), H.264 High Profile, and proprietary codecs from manufacturers such as Microsoft (RTvideo).

H.264 SVC is based on the idea of slicing individual frames into layers, with each layer holding part of a single frame's image. H.264 SVC sessions still provide high quality, even if endpoints are able to exchange only a small percentage of layered frames. High Profile reduces bandwidth requirements, achieving up to a 50 percent reduction in bandwidth compared with H.264 Advanced Video Coding.