* Do vendor moves reflect on Vo-Fi’s maturity?
There have been several announcements by Wi-Fi vendors and vendor partners recently making product enhancements related to QoS for Wi-Fi voice. These should be reassuring. But instead, they make me wonder what’s wrong with 802.11e.
802.11e is the emerging Vo-Fi QoS standard poised for ratification in October. Of course, it’s been on the brink of ratification for about six years now, so interpret that how you will.
My discomfort is that if partners have to ally to make their voice and Wi-Fi products work together and if Wi-Fi vendors must make special modules for their controllers to ensure voice quality, just how mature is Vo-Fi technology? How tough is it going to be for enterprises to implement and manage Vo-Fi throughout their organizations and feel confident that it will work well and consistently – particularly if they deploy a mix of vendors’ handsets and softphones?
Last week, for example, Intel and Avaya announced a partnership to optimize Avaya’s SIP-based softphone implementation for Intel’s next Centrino mobile laptop technology, codenamed “Napa.” The joint optimization activity entails packet prioritization, bandwidth reservation and call admission control.
But much of this is specified in the forthcoming 802.11e standard. So what gives? Dave LeClair, director of technology partnerships in Avaya’s appliances division, conceded that the partnership indeed simply entails “pushing the 802.11e standards along at a quicker pace.”
Prior to that announcement, voice-centric Wi-Fi vendor Meru Networks announced a Voice Services Module for its Wi-Fi system. The software conducts important activities such as call admission control, call load balancing among access points (AP) and dynamic error detection.
But, unlike LeClair, Meru Director of Product Marketing Joel Vincent asserts that “802.11e is not sufficient” for large-scale Vo-Fi QoS.
“802.11e operates by providing QoS parameters to the clients attached to a single AP. Neighboring APs are not… coordinating priorities between each other. When they are not coordinated they will collide” in large enterprises, he says.
Meru’s architecture places multiple physical APs on a single channel to form one large “virtual AP” so that, in effect, there is no inter-AP roaming or coordination to deal with. On the other hand, there are bandwidth limitations to the single-channel-sharing architecture. Meru announced a product called the Radio Switch, which combines up to 12 channels in one controller for denser deployments, in May.
For Wi-Fi architectures making use of multiple RF channels, the 802.11-standard roaming, pre-authentication, and radio resource management capabilities discussed in the last newsletter will likely be needed, along with 802.11e, for the coordination that Vincent describes.
