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Cisco AVVID Network Infrastructure Enterprise Quality of Service Design

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QoS Considerations When Connecting
End-Points to an AVVID Network

This chapter provides information about implementing QoS at the edge of an AVVID network. It
includes the following:

Mission-Critical Applications

Summary

Note

This chapter contains references to other documents. These references are included as tips in the text.
The URL for each referenced document is located in

Appendix A, "Reference Information."

In some

cases, an internal document is referenced. For copies of internal documents, please see your Cisco
Systems representative.

Overview

Classification (or marking) of traffic at the edge of the network (where CPU resources are plentiful and
scalability of classification services is not an issue) is a requirement that needs to be addressed in today's
enterprise networking environments.

This chapter focuses on the design requirements at the edge of the network needed to classify traffic so
that devices throughout the network can recognize loss, delay, and delay variation sensitive applications
and give them the appropriate treatment end-to-end.

Throughout this chapter VoIP traffic will be used to illustrate how QoS can limit loss, delay, and delay
variation because it is easy to illustrate how network performance can adversely affect voice quality.
Delay-sensitive applications, like video-conferencing over IP, and mission critical applications, like
ERP applications or mainframe SNA applications, have similar requirements of the network and are
adversely affected by packet loss, delay, and delay variation.