1
Scope
2
References
3
Definitions
3.1
Terms defined elsewhere
3.2
Terms defined in this Recommendation
4
Abbreviations and acronyms
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
6.5 PNT
domain and CES domain
7 Reference timing signal distribution over
packet networks (PNT domain)
7.1
Plesiochronous and network synchronous methods
7.2
Packet-based methods
8
Timing recovery for constant bit rate services transported over packet
networks (CES domain)
8.1
Network synchronous operation
8.2
Differential methods
8.3
Adaptive methods
8.4
Reference clock available at the TDM end systems
9
Network limits
9.1
CES network limits
9.2
PNT network limits
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 the service clock recovery
11.1
Impairments for the network synchronous operation methods
11.2
Impairments for the differential method
12
Results and consequences of the different synchronization methods over
packet network reference models
12.1 CES
domain recommendations
12.2 PNT
domain recommendations
Annex A – Proposed network architecture for synchronous Ethernet
A.1
PRC Location
A.2
Limiting jitter and wander of synchronous Ethernet
A.3
Considerations on the design of synchronization network based on
synchronous Ethernet
A.4
Example of timing distribution via synchronous Ethernet
A.5
Interworking of Ethernet and synchronous Ethernet interfaces
Annex B – IWF functional partitioning into CES and PNT IWF and network
examples
B.1
General
B.2
IWF clocks
B.3
Network examples
Annex C – CES IWF synchronization related requirements
C.1
Traffic interfaces
C.2
Synchronization interfaces
C.3
IWF synchronization function
Annex D – Network applications and requirements for clocks specified in
ITU-T G.8262/Y.1362
Appendix I – Characteristics of Ethernet switches, Ethernet networks,
routers and access technologies
I.1
Characteristics of Ethernet switches and networks
I.2
Delay characteristics of routers
I.3
Delay characteristics of access technologies (Microwave nodes, PON, DSL)
Appendix II – Stabilization period
Appendix III – Considerations on packet-based methods
Appendix IV – Applications and use cases
IV.1
Background
IV.2
Wireless
IV.3
Infrastructure
IV.4
Media gateway
Appendix V – Packet networks reference models
V.1
Ethernet networks models
V.2
Other network models
Appendix VI – Measurement guidelines for packet-based methods
VI.1
Measurement reference points
VI.2
Input traffic characteristics
VI.3
Test topologies for adaptive methods
VI.4
Test Topologies for differential methods
VI.5
Test for two-way protocols
Appendix VII – Wander limits in Deployment Case 1
VII.1
Limits for the 2048 kbit/s interface
Page
VII.2
Limits for the 1544 kbit/s interface
Appendix VIII – Synchronization status messaging in synchronous Ethernet
PHY
Appendix IX – IWF examples
Appendix X – Considerations on measurement of synchronous Ethernet
according to ITU-T methodologies in comparison with IEEE jitter measurements
Appendix XI – Relationship between requirements contained in this
Recommendation and other key synchronization related Recommendations
Appendix XII – Basic principles of timing over packet networks
XII.1
General
XII.2
Packet delay variation mitigation by packet selection
XII.3
Comparison of packet-based and synchronous PHY methods
XII.4
Existing standards
Appendix XIII – Evaluation of the packet delay variation generation in a
network node
XIII.1
Introduction
XIII.2
General considerations
XIII.3 General
configuration
Bibliography