Quality of Service Platform

Applies To: Windows Server 2008 R2

The Windows Vista developer platform for network Quality of Service (QoS) consists of a user-mode application programming interface (API), available from Qos2.h and qwave.dll, and a kernel-mode packet scheduler (Pacer.sys), which manages QoS flows created by using the user-mode API.

The Windows Vista QoS API supports the differentiated services discipline in that:

  • Layer 3 Differentiated Service Code Points (DSCPs) can be set in the IPv4/IPv6 packet header
  • Layer 2 802.1p tags can be added to the Ethernet frame header
  • Send-rate throttling can be applied

This API is applied at a network socket level. Multimedia scenarios on Windows-based clients (not servers) are enabled by using this platform to provide end-to-end bandwidth estimation and congestion detection for network IP traffic that uses either TCP or UDP.

Managed Entities

The following is a list of the managed entities that are included in this managed entity:

Name Description

Policy-based Quality of Service (QoS)

Quality of Service (QoS) in Windows Server 2008 and Windows Vista helps to reduce network congestion and optimize bandwidth by providing centralized management of traffic sent by network hosts.