User guide

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Security
device with the requisite level of QoS and correct feature sets — making it ideal for deliv-
ery of triple play voice, video, and data services.
VGx was developed to ensure that subscribers receive the quality of voice, video, and data
services they expect — to prevent a large data download from causing jittery video or poor
voice quality. VGx achieves this goal by providing superior service segmentation and QoS
features obtained by mapping multiple local virtual local area networks (VLANs) to one or
more specific permanent virtual circuits (PVCs) for DSL, or wide area network VLANs for a
fiber network.
Traffic prioritization is determined through the Institute of Electrical Engineering (IEEE)
standard 802.1p, which specifies QoS algorithms to prioritize traffic based on protocol and
source. This insures that each service receives the QoS treatment it requires; for example,
• video is free from latency,
• VoIP service is prioritized to insure aural quality, and
• data is securely and efficiently routed.