(Optional) Configuring G.8275.1 Message Attributes

Context

G.8275.1 devices periodically send or receive G.8275.1 messages to establish the master-slave hierarchy and transmit time information. G.8275.1 messages include Announce messages and Delay messages. Announce messages are used to exchange time synchronization information between G.8275.1 devices and establish the master-slave hierarchy. Delay messages are event messages, which are timestamped when reaching or leaving a G.8275.1 device to measure the link delay.

If a G.8275.1 device requires high-precision clock synchronization and needs to trace the master clock frequency, reduce the interval for sending G.8275.1 messages. However, this consumes more bandwidth resources. If the sending link delay and receiving link delay are different, you can configure correction for sending or receiving G.8275.1 messages to correct the link delay.

Procedure

Configure attributes for Announce messages.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view is displayed.
3. Run ptp announce-interval announce-interval
  The interval for sending Announce messages on the interface is set to 2^{announce-interval}, in milliseconds.
  The default value of announce-interval is 7, indicating that the interval for sending Announce messages on an interface is 128 ms.
  If announce-interval is set to a small value, G.8275.1 devices frequently exchange G.8275.1 messages, consuming more bandwidth resources. If announce-interval is set to a large value, high-precision clock synchronization cannot be guaranteed; however, clock synchronization accuracy can be guaranteed.
4. Run ptp announce receipt-timeout timeout-value
  The maximum number of timeouts for receiving Announce messages is set.
  
  By default, the maximum number of timeouts for receiving Announce messages is 3.
Configure attributes for G.8275.1 Delay messages.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view is displayed.
3. Run ptp sync-interval sync-interval
  The interval for sending Sync messages is configured on an interface.
  
  By default, the interval for sending Sync messages is 64 ms.
4. Run ptp min-delayreq-interval min-delayreq-interval
  The interval for sending DelayReq messages on the interface is set to 2^{min-delayreq-interval}, in milliseconds.
  The default value of min-delayreq-interval is 6, indicating that the interval for sending DelayReq messages on the interface is 64 ms.
5. Run ptp asymmetry-correction { positive | negative } asymmetry-correction
  The asymmetric correction for sending G.8275.1 event messages is configured on the interface.
  By default, no asymmetric correction for sending G.8275.1 event messages is configured because G.8275.1 devices consider that the sending link delay and receiving link delay are the same.