Meru Networks introduced a new plug-in software module for its Wireless LAN System that enables the deployment of large, pervasive wireless VoIP networks. The Meru WLAN System can now protect existing calls on the network and guarantee optimal service quality without any dependence on proprietary extensions to the client or proprietary signaling from the IP-PBX. It also can provide dynamic error correction for voice calls.
The new Voice Service Module delivers three key features, that when used with the Meru WLAN System's Virtual Cell capability, make the deployment and operation of voice over WLAN networks increase call capacity and improve the call quality. VSM transparently balances clients and calls across access points and optimizes call quality by denying overflow calls from any 802.11 VoIP device without depending upon the IP-PBX used. The key features are as follows:
- Call Admission Control: Allows the Meru WLAN System to actively limit the calls that can be made on an area of the network at any one time, preventing additional calls from damaging the service quality of the network. Admits and presents "network busy" tones based on available resources to provide a carrier grade handling of network overload similar to the Public Switched Telephone Network. Works independently of the IP-PBX so that enterprises can select handsets and IP-PBXs without any regard to the WLAN infrastructure.
- Call Balancing: Eliminates the contention, collisions, and generally unpredictable service quality that occur with traditional WLAN systems. Enables the Meru WLAN System to actively manage a global map of VoIP call loads and balance the active voice clients across the network. VoIP client thresholds can be set on a per access point and per Virtual Cell basis so the system can optimally balance calls throughout the network. This allows the network operator to overlay channels in an area, thus allowing 3-4 times the call density in a single area as multiple Virtual Cells can be overlayed and calls balanced between them.
- Enhanced Call Flow Detection: The Meru VSM, using application flow detection capabilities, automatically detects call setup resources as required for the compression/decompression (CODEC) algorithm and protocol being used, provisions over-the-air QoS for that call and admits the call as per the call admission policies. This capability is available for a broad range of client handset protocols, including SIP, H.323, Cisco Skinny Call Control Protocol (SCCP), Spectralink SVP and Vocera.
- Dynamic Error Correction: Works with the Meru WLAN System's patented Air Traffic Control technology to deliver enhanced over-the-air QoS, preventing voice calls from being lost and voice quality from being degraded. As an optional on/off feature, VSM Dynamic Error Correction allows the system to recognize when voice packets have been lost, inserting a predictive sample into the voice flow, keeping the signal continuous and preventing the receiving client from hearing gaps in the voice calls.
