Meru Announces Utility to Optimize Video Delivered over Wireless
- By Dian Schaffhauser
Meru Networks has introduced a wireless local area network product optimized for delivering high-quality video over 802.11n networks running its System Director software. Meru's Video Services Module (ViSM) is designed to address video-delivery issues specific to 802.11n networks, which, the company said, are susceptible to unpredictable loss rates that can impair video quality. The module applies application-aware optimization techniques to Web streaming and real-time multicast video, the technologies used for such uses as videoconferencing, telepresence, and video surveillance.
"Video-based applications are becoming pervasive in schools, health-care institutions and other enterprises because they boost productivity significantly for a relatively low cost," said Vaduvur Bharghavan, Meru's chief technology officer. "But high-definition video delivery over wireless is especially challenging because it combines the high bandwidth requirements of heavy data traffic with the delay sensitivity and loss characteristics of voice traffic. And while 802.11n dramatically increases available bandwidth, it also increases per-transmission error rates. For multicast applications this translates to lost portions of video; for Web video streaming it can mean stalled video or the loss of voice-video synchronization.
The Meru Video Services Module uses several mechanisms to deliver video traffic based on application and user characteristics, allowing scaling to large numbers of concurrent video sessions.
Application-aware prioritization synchronizes the voice and video components of a video stream, adapting the delivery of each frame based on its importance to the application. Higher-priority MPEG-4 AVC/H.264 marked frames are transmitted with greater assurance of reliability and timeliness.
- User- and role-based policy enforcement provides control over application behavior. For example, faculty video access can be assigned higher priority than students.
- Handoff reroutes delivery to prevent lost video frames during a transition between access points and maximizes zero-loss for mobile video.
- Multicast group management optimizes delivery to only those virtual ports whose clients are members of the multicast group.
- Graphical visualization shows which clients are running which applications (data, voice, and video) to aid in monitoring network-wide application performance.
Several customers have been using Meru video optimization techniques on their Meru 802.11a/b/g WLANs and plan to deploy the new Video Services Module.
Jason Hyams, director of technology at St. Agnes Academy in Houston, TX, has used the school's Meru WLAN to support wireless projection in the classrooms for up to 700 concurrent users. "Using WLAN projectors means a huge saving for new classrooms. It gives us the flexibility to use the Internet, TV and whiteboard sessions all from one piece of equipment. Teachers can move around with their laptops and project everything from YouTube to PowerPoint. We will soon be deploying 11n for the first time in our science classrooms, and will look to the Meru WLAN to support new video applications and services as reliably as it has on 11a/b/g."
The Meru Video Services Module will be available in June 2009 as an add-on to Meru's System Director software. System Director, which can already be combined with modules for voice services and policy enforcement, is embedded in Meru's controllers and access points. For a network with 100 wireless access points, the new module is priced at $7,995.
Dian Schaffhauser is a senior contributing editor for 1105 Media's education publications THE Journal and Campus Technology. She can be reached at firstname.lastname@example.org or on Twitter @schaffhauser.