Cisco Systems 416 Manual De Usuario

C H A P T E R

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In an Architecture for Voice, Video, and Integrated Data (AVVID) network, you must configure QoS for 
IP telephony to ensure voice quality. 

The following topics provide information about the need for configuring QoS in an IP telephony 
environment and the tools that enable you to do this.

Real-time based applications in a network, such as voice applications, have different characteristics and 
requirements than those of data applications. Voice applications tolerate minimal variation in the amount 
of delay affecting delivery of their voice packets. 

Voice traffic is also intolerant of packet loss and jitter, both of which degrade the quality of the voice 
transmission delivered to the recipient end user. To effectively transport voice traffic over IP, 
mechanisms are required that ensure reliable delivery of packets with low latency.

In an enterprise environment, network congestion can occur at any time in any portion of the network 
campus, branch office, or WAN. For successful deployment of IP telephony, you must ensure end-to-end 
network quality for voice traffic.

To ensure voice quality, you must use QoS in all areas of the enterprise network. To make a proper QoS 
configuration, you must first identify the points where QoS is a concern, then choose the appropriate 
QoS tools to use, and deploy to the devices in the network.