PrefaceThe H3C S5120-EI documentation set includes 10 configuration guides, which describe the softwarefeatures for the S5120-EI Series Ethernet Switches and guide you through the software configurationprocedures. These configuration guides also provide configuration examples to help you apply softwarefeatures to different network scenarios.The ACL and QoS Configuration Guide describes fundamentals and configuration of ACL and QoS. Itdescribes how to create IPv4 ACL and IPv6 ACL, use ACL for packet filtering, use QoS polices tocontrol traffic, and configure common QoS techniques such as traffic policing, traffic shaping, andcongestion management.This preface includes:z Audiencez Document Organizationz Conventionsz About the H3C S5120-EI Documentation Setz Obtaining Documentationz Documentation FeedbackAudienceThis documentation set is intended for:z Network plannersz Field technical support and servicing engineersz Network administrators working with the S5120-EI seriesDocument OrganizationThe ACL and QoS Configuration Guide comprises these parts:ACL Configuration QoS Overview QoS ConfigurationApproachesPriority MappingConfigurationTraffic Policing, TrafficShaping, and Line RateConfigurationCongestion ManagementConfigurationTraffic FilteringConfigurationPriority MarkingConfigurationTraffic RedirectingConfigurationClass-Based AccountingConfigurationAppendix A DefaultPriority Mapping TablesAppendix B Introductionto Packet PrecedencesConventionsThis section describes the conventions used in this documentation set.Command conventionsConvention DescriptionBoldface Bold text represents commands and keywords that you enter literally as shown.italic Italic text represents arguments that you replace with actual values.