Cisco Systems A9014CFD PTP Boundary Clock, Configures Cisco ASR 901 router on unicast, 22-26

Chapter 22 Configuring Clocking

Configuring PTP for the Cisco ASR 901 Router

The command used for configuring Cisco ASR 901router on unicast negotiation mode is clock-port.

Command	Purpose
Router(config-ptp-clk)# clock-port	Configures Cisco ASR 901 router on unicast
	negotiation mode. The following options can be
	configured with this command:
	•	Port Name
	•	Port Role

The following example shows the configuration of Cisco ASR 901 router on the unicast negotiation mode:

Router# configure terminal

Router(config)# ptp clock ordinary domain 0

Router(config-ptp-clk) clock-port SLAVE slave

Router(config-ptp-port)#transport ipv4 unicast interface loopback 23 negotiation

Router(config-ptp-port)# clock-source 8.8.8.1

Router(config)# ptp clock ordinary domain 0

Router(config-ptp-clk)# clock-port MASTER Master

Router(config-ptp-port)#transport ipv4 unicast interface loopback 23 negotiation

Router(config-ptp-port)# sync interval <>

Router (config-ptp-port)# announce interval <>

PTP Boundary Clock

A PTP boundary clock (BC) acts as a middle hop between a PTP master and PTP slave. It has multiple ports which can act as a master or slave port as shown in Figure 22-1. A PTP boundary clock has one slave port and one or more master ports. A slave port acts as a slave to a remote PTP master, while a master port acts as a master to a remote PTP slave. A PTP boundary clock derives clock from a master/grand master clock (by acting as a slave) and sends the derived clock to the slaves connected to it (by acting as a master).

PTP boundary clock starts its own PTP session with a number of downstream slaves. The PTP boundary clock mitigates the number of network hops and results in packet delay variations in the packet network between the grand master and slave.

Figure 22-1	PTP Boundary Clock
				PTP Slaves
			PTP Boundary	S
PTP Master			M
	M	S	M	S
			M

M - Master Port	S
S - Slave Port

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	Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide
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