Title: Timing characteristics of Telecom Boundary Clocks (T-BC) and Telecom Slave Clocks (T-TSC)

Summary

Clock specification for T-BC (boundary clock) and T-TSC (time slave clock) for full timing support architecture, including noise tolerance, noise generation, noise transfer, phase transients
Four clock types defined, classes A to D:
- Class A intended for short chains (up to 10 clocks), to meet ±1.5µs overall requirement
- Class B intended for long chains (up to 20 clocks) , to meet ±1.5µs overall requirement
- Class C intended for long chains (up to 20 clocks), suitable for fronthaul applications
- Class D intended for long chains, delivered over new interface types (e.g. FlexE, FlexO) with special provision for low-noise timing transmission

Current version: 2nd. Edition, October 2020, plus Amd. 1, Feb 2022 and Amd. 2, Nov 2022
Download from: http://www.itu.int/ITU-T/recommendations/rec.aspx?rec=13109

Parameter	Conditions	Class A	Class B	Class C	Class D
Max \|TE\|	Unfiltered, 1000s	100ns	70ns	30ns	-
Max\|TE_L\|	0.1Hz low-pass filter,1000s	-	-	-	5ns
cTE	Averaged over 1000s	50ns	20ns	10ns	-
dTE_L MTIE	0.1Hz low-pass filter, Const. temp, 1000s	40ns	40ns	10ns	-
	0.1Hz low-pass filter, Var. temp, 10000s	40ns	40ns	10ns	-
dTE_L TDEV	0.1Hz low-pass filter, Const. temp, 1000s	4ns	4ns	2ns	-
dTE_H	0.1Hz high-pass filter, Const. temp, 1000s	70ns	70ns	30ns	-

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