802.11n Video Service Module (ViSM)
Video streaming has the low latency and loss requirements of with the high-throughput requirements of data. The Fortinet Video Service Module
(ViSM) is an optional licensed software module that delivers predictable 802.11 video performance with minimal delay, latency and jitter. Sustainable high data rates, even in mixed traffic, are supported along with synchronization of video and audio transmissions.
ViSM also introduces additional mechanisms for optimizing unicast and multicast video such as application aware scheduling, /video synchronization, and client-specific multicast group management. Features include the following:
- High throughput with low burstiness offers predictable performance and consistent user experience
- Application-aware prioritization synchronizes the and video components of a video stream, adapting the delivery of each frame based on its importance to the application.
802.11n Video Service Module (ViSM)
- Multicast group management optimizes delivery to only those Virtual Ports whose clients are members of the multicast group.
- Seamless video-optimized handoff proactively reroutes the multicast delivery tree to prevent lost video frames during a transition between access points and ensures zero loss for mobile video.
- User and role based policy enforcement provides granular control over application behavior.
- Visualization reveals which clients are running which applications.
Implementing ViSM
Virtual Port already changes multicast to unicast transmissions. ViSM adds per-client IGMP Snooping to the transmission. Therefore, to implement ViSM, turn on IGMP Snooping. CLI commands control IGMP snooping (see FortiWLC (SD) Command Reference). At this time, ViSM licensing is not enforced.