1
Scope
2 References
3 Definitions
3.1 Terms defined
elsewhere
3.2 Terms defined in this
Recommendation
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
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 G.8262/Y.1362
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 –
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
VII.2 Limits for the 1544
kbit/s interface
Appendix VIII – Synchronization status messaging in
synchronous Ethernet PHY
Appendix IX – IWF examples
Page
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
Bibliography