Recommendation ITU-T G.8260 Amd.1 (01/2024) Definitions and terminology for synchronization in packet networks 
1 Scope
2 References
Summary
History
FOREWORD
Table of Contents
3 Definitions
     3.1 Terms defined in this Recommendation
4 Abbreviations and acronyms
5 Conventions
6 Description of packet timing concepts
     6.1 The nature of packet timing
     6.2 Differences between packet-based and physical layer timing systems
     6.3 Classes of packet clocks
     6.4 Two-way timing protocols
     6.5 Packet delay sequence measurement
     6.6 Packet timing signal equipment interface characterization
Appendix I  Definitions and properties of packet measurement metrics
     I.1 Introduction
     I.2 Definition of the time error sequence
     I.3 Packet selection and filtering
          I.3.1 Packet selection types
               I.3.1.1 Pre-processed packet selection
               I.3.1.2 Pre-processed packet filtering
               I.3.1.3 Integrated packet selection
               I.3.1.4 Packet selection windows
          I.3.2 Packet selection methods
               I.3.2.1 Minimum packet selection method
               I.3.2.2 Percentile average packet selection method
               I.3.2.3 Band average packet selection method
               I.3.2.4 Cluster range packet selection method
          I.3.3 Consideration of non-stationary network conditions
          I.3.4 Two-way time error calculation
     I.4 PDV metrics estimating the performance of a packet slavetimeReceiver clock
          I.4.1 Metrics estimating phase wander
               I.4.1.1 Maximum average time interval error
               I.4.1.2 minMATIE
               I.4.1.3 pktfilteredTIE
               I.4.1.4 pktfilteredMTIE
          I.4.2 Metrics estimating frequency stability
               I.4.2.1 TDEV-based metrics
                    I.4.2.1.1 MinTDEV
                    I.4.2.1.2 PercentileTDEV
                    I.4.2.1.3 BandTDEV
                    I.4.2.1.4 ClusterTDEV
                    I.4.2.1.5 pktfilteredTDEV
          I.4.3 Metrics estimating frequency accuracy
               I.4.3.1 Maximum average frequency error
                    I.4.3.1.1 Pros and cons of MAFE and MATIE
               I.4.3.2 minMAFE
               I.4.3.3 pktfilteredFFO
          I.4.4 Metrics estimating time error
               I.4.4.1 Packet-selected two-way time error (pktSelected2wayTE)
               I.4.4.2 Packet filtered two-way time error (pktFiltered2wayTE)
               I.4.4.3 Maximum/Minimum/Peak-to-peak average time error (maxATE, minATE, ppATE)
     I.5 PDV metrics studying floor delay packet population
          I.5.1 Determination of observed floor delay
               I.5.1.1 Minimum floor delay over the entire measurement
               I.5.1.2 Progressive determination of floor delay
               I.5.1.3 Re-route events and impact on observed floor delay
                    I.5.1.3.1 Re-route events
                    I.5.1.3.2 Re-route event impact on packet network limit
                    I.5.1.3.3 Determination of re-route event
                    I.5.1.3.4 Determination of re-route events using an OFD estimation method
          I.5.2 Use of floor delay packet population PDV metrics for two-way protocol flows
          I.5.3 Exceptional events and impact on packet network limit
Appendix II  Time scales
     II.1 Universal time (UT)
     II.2 International atomic time (TAI)
     II.3 Coordinated universal time (UTC)
Appendix III  Clarifications on the term traceability
Bibliography