Netgear M5300-52G3 Software Administration Manual - Page 193

12. DiffServ Differentiated Services 12 This chapter provides the following examples: • DiffServ on page 194 • DiffServ for VoIP on page 210 • Auto VoIP on page 217 • DiffServ for IPv6 on page 221 • Color Conform Policy on page 228 Differentiated services (DiffServ) is one technique for implementing Quality of Service (QoS) policies. Using DiffServ in your network allows you to directly configure the relevant parameters on the switches and routers rather than using a resource reservation protocol.This section explains how to configure the 7000 Series Managed Switch to identify which traffic class a packet belongs to, and how it should be handled to provide the quality of service you want. As implemented on the 7000 Series Managed Switch, DiffServ allows you to control what traffic is accepted and what traffic is discarded. How you configure DiffServ support on a 7000 Series Managed Switch varies depending on the role of the switch in your network: • Edge device. An edge device handles ingress traffic, flowing toward the core of the network, and egress traffic, flowing away from the core. An edge device segregates inbound traffic into a small set of traffic classes, and is responsible for determining a packet's classification. Classification is based primarily on the contents of the Layer 3 and Layer 4 headers, and is recorded in the Differentiated Services Code Point (DSCP) added to a packet's IP header. • Interior node. A switch in the core of the network is responsible for forwarding packets, rather than for classifying them. It decodes the DSCP code point in an incoming packet, and provides buffering and forwarding services using the appropriate queue management algorithms. Before configuring DiffServ on a particular 7000 Series Managed Switch, you must determine the QoS requirements for the network as a whole. The requirements are expressed in terms of rules, which are used to classify inbound traffic on a particular interface. The switch software does not support DiffServ in the outbound direction. Rules are defined in terms of classes, policies, and services: Chapter 12. DiffServ | 193