Vendors attempt to improve network control for video delivery
There’s quite a buzz about corporations getting into video or “content delivery.” These efforts involve large files, real-time QoS requirements and significant bandwidth consumption. Within enterprises, the most popular uses for video are collaborative meetings and streaming content for online training or executive speeches and messages.
Given that many internal workers are now connected wirelessly via Wi-Fi it might be important to have a conversation with your wireless WLAN vendor about what, if anything, it does “special” to reliably support video.
For its part, Cisco last Tuesday announced VideoStream, a bundle of three access point (AP) technologies intended to improve video quality. First, it converts multicast sessions into unicast sessions, turning the AP, in part, into a mini content-delivery server. Aruba Networks and Ruckus Wireless also reportedly have such technology and Ruckus has, since its inception as a Wi-Fi provider for delivering IP TV, touted its proprietary dynamic beamforming as a key contributor to high-quality video.
The second component of Cisco VideoStream borrows the “call admission control” concept from voice networks. It delivers the equivalent of a busy signal if the addition of one more session to the wireless pipe would degrade those already in progress. Cisco calls this blocking for video protection “Resource Reservation.”
“We’re taking our voice enhancements and adding ‘video nuances,'” says David Stiff, a product manager in Cisco Wireless Networks Business Unit. “We’re not climbing the whole mountain again.”
He adds that VideoStream also creates another layer of granularity to prioritizing video streams. Generally, all video gets classified into a common class, with all video streams treated equally in the priority pecking order. Stiff says, though, that users can now prioritize one video stream over another fairly easily (e.g., the president’s message over a random YouTube download).
Interestingly, Cisco showed comparative VideoStream performance results based on testing by Miercom, which pitted Cisco against Aruba and Motorola. Be advised that vendors choose whom they want to be compared to based in part on who they want the industry to think they compete most directly with and, also, often in terms of who they figure they can beat. It was interesting that the performance testing didn’t include video-centric Ruckus or Meru Networks, whose centrally controlled, no-handoff, and, most recently, service-assurance-enabled networks do a strong job of content delivery.
