ITU-T Recommendations

This Recommendation defines classes of network Quality of Service (QoS), and specifies provisional objectives for Internet Protocol network performance parameters. These classes are intended to be the basis for agreements among network providers, and between end users and their network providers. Appendix I provides information about how ATM might support IP layer performance. Appendix II discusses alternatives for defining IP delay variation. The material in Appendix II will eventually be incorporated into ITU-T Rec. Y.1540. Appendix III presents the Hypothetical Reference Paths against which the Y.1541 QoS objectives were tested for feasibility. Appendix IV gives example computations of packet delay variation. Appendix V discusses issues that must be considered whenever IP measurements are made. Appendix VI describes the relationship between this Recommendation and the IETF defined mechanisms for managing QoS. Appendix VII discusses the packet transfer delay objective and how it relates to other Recommendations. Appendix VIII presents a Bibliography. Appendix IX discusses potential applications of IP Networks.