CONTENTS

 1     Scope     
 2     References     
 3     Definitions     
 4     Abbreviations     
 5     Conventions     
6 General     
        6.1 Packet network synchronization requirements     
        6.2 TDM timing requirements     
        6.3 Synchronization network engineering in packet networks     
        6.4 Timing requirements at edge versus timing requirements in core networks     
7 Network limits     
        7.1 Network model underlying the network limits     
8 Reference timing signal distribution over packet networks     
        8.1 Plesiochronous and network-synchronous methods     
        8.2 Packet-based methods     
9 Timing recovery for constant bit rate services transported over packet networks     
        9.1 Network-synchronous operation     
        9.2 Differential methods     
        9.3 Adaptive methods     
        9.4 Reference clock available at the TDM end systems     
10 Impact of impairments in the packet network on timing distribution and service clock recovery     
       10.1 Packet Transfer Delay and Delay Variation     
       10.2 Impacts from packet impairments     
11 Impact of the reference clock impairment on timing distribution and service clock recovery     
       11.1 Impairments for the network-synchronous operation methods     
       11.2 Impairments for the differential method     
12 IWF synchronization-related requirements     
       12.1 Traffic interfaces     
       12.2 Synchronization interfaces     
       12.3 IWF synchronization function     
13 Results and consequences of the different synchronization methods over packet network reference models     
       13.1 Recommendations for Deployment Case 1     
       13.2 Recommendations for Deployment Case 3     
       13.3 Recommendations for Deployment Case 2 Application A     
       13.4 Recommendations for Deployment Case 2 Application B     
nnex A � Proposed network architecture for synchronous Ethernet PHY
        A.1 PRC location     
        A.2 Synchronization Status Messaging     
        A.3 Limiting jitter and wander of synchronous Ethernet     
Appendix I � Characteristics of Ethernet switches and networks     
        I.1      Delay characteristics of Ethernet switches     
        I.2      Characteristics of switched Ethernet networks     
Appendix II � Stabilization period     
Appendix III � Functional models based on ITU-T Recs G.805 and G.809     
III.1 Application of ITU-T Rec. G.805 to the IWF
III.2 Timing information transported over layer networks     
III.3 Functional model of Ethernet physical layer timing     
III.4 Functional model for differential and adaptive methods     
Appendix IV � Synchronization aspects at the edge of the network     
IV.1 Synchronization requirements for GSM, WCDMA and CDMA2000 Base Stations     40
Appendix V � Packet networks reference models     
Appendix VI � Measurement guidelines     
VI.1 Measurement reference points     
VI.2 Test topologies     
Appendix VII � Wander limits in Deployment Case 1     
VII.1 Limits for the 2048 kbit/s interface     
VII.2 Limits for the 1544 kbit/s interface     
Appendix VIII � Synchronization Status Messaging in synchronous Ethernet PHY
VIII.1 Synchronization Operations & Maintenance     
VIII.2 Synchronization Status Messaging     
VIII.3 New Ethernet equipment     
VIII.4 Legacy Ethernet equipment     
BIBLIOGRAPHY