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Cisco AVVID Network Infrastructure Enterprise Quality of Service Design
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Overview
This chapter provides an overview of Quality of Service (QoS) and its uses. This chapter provides
high-level answers to the following questions:
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Note
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Why is Quality of Service Required for AVVID?
The key enabling technology for network convergence in the Architecture for Voice, Video, and
Integrated Data (AVVID) is QoS. This is because voice, video, and mission-critical data have stringent
service requirements from the network infrastructure. These requirements supersede the requirements of
generic data traffic. If voice, interactive-video, and mission-critical data are not given priority service
from network devices, then the quality of these important applications would quickly degrade to the
point of being unusable.
Understanding QoS
QoS is defined as the measure of performance for a transmission system that reflects its transmission
quality and service availability. Service availability is a crucial foundation element of QoS. Before any
QoS can be implemented successfully, the network infrastructure must be designed to be highly
available. The transmission quality is determined by the following factors:
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There are many points in AVVID networks where QoS mechanisms are required to manage loss, delay,
and delay variation.
illustrates areas where QoS mechanisms are required to control the
impact of loss, delay, and delay variation on voice performance.