Qg 2 Multi-Sync Gateway User Guide
Managed Clock Engine Overview
SJC-DEV7250-HR Rev. 1.14
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6.7.5.2
SyncE in Boundary Clock Mode for G8275.2 Telecom Profile
G8275.2 profile is specified for L3 unicast network and is based on partial timing support from the
network. This means that not all network nodes may participate in PTP protocol. In this mode, SyncE
input frequency reference can be used as a frequency-assist for PTP. The physical layer (ie. frequency)
output is controlled by both, the input (from SyncE) and PTP engine. Unlike in G8275.1, here the physical
layer output is NOT directly from input reference and hence not traceable and cannot be used for SyncE
output distribution. SyncE output is disabled in this case.
The figures below show the flexibility of specifying the ports for operation in this mode.
Figure 21 SyncE in BC mode for G8275.2, ref input on Port-1
Figure 22 SyncE in BC mode for G8275.2, ref input on Port-2
6.7.6
SyncE – additional notes
Some additional notes regarding SyncE feature in Ts2:
1.
Synchronous Ethernet is supported only for 1GE interface speed. If user had configured
previously on Interfaces::PTP webpage for a different Auto-Negotiation and speed parameters,
they will be reset to 1000Mbps Full-duplex.
2.
Support for enhanced EEC (eEEC) bandwidth options will be supported in future release
3.
For other profiles besides G8275.1 and G8275.2, the SyncE operation will depend on whether
the profile is specified for L2-multicast or L3-unicast. If L2-multicast, then it will follow G8275.1
operation, and if L3-multicast, it will follow G8275.2 operation.
4.
SyncE operation is valid only in association with Operating Modes, GNSS-only and PTP-only.
Synchronous Ethernet field should be set to off for other operating modes.
Ts2
Managed
Timing Engine
SyncE (output)
DISABLED
SyncE (input)
ENABLED
Port-1
Port-2
Ts2
Managed
Timing Engine
SyncE (output)
DISABLED
SyncE (input)
ENABLED
Port-2
Port-1
