ptp announce-interval

Function

The ptp announce-interval command sets the interval at which a PTP interface sends Announce packets.

The undo ptp announce-interval command restores the default interval.

The default interval at which a PTP interface sends Announce packets is 128/1024s.

In PTP mode except SMPTE-2059-2, the default value is 7. In SMPTE-2059-2 mode, the default value is 8.

Format

ptp announce-interval announce-interval

undo ptp announce-interval

Parameters

Parameter	Description	Value
announce-interval	Specifies the interval at which Announce packets are sent.	The value is an integer. The value range depends on the board type. The mapping between announce-interval values and actual intervals is as follows: 0 1/1024s 1 2/1024s 2 4/1024s 3 8/1024s 4 16/1024s 5 32/1024s 6 64/1024s 7 128/1024s 8 256/1024s 9 512/1024s 10 1s 11 2s 12 4s 13 8s 14 16s 15 32s 16 64s 17 128s 18 256s 19 512s 20 1024s

Parameter

Description

Value

announce-interval

Specifies the interval at which Announce packets are sent.

The value is an integer. The value range depends on the board type. The mapping between announce-interval values and actual intervals is as follows:

0 1/1024s
1 2/1024s
2 4/1024s
3 8/1024s
4 16/1024s
5 32/1024s
6 64/1024s
7 128/1024s
8 256/1024s
9 512/1024s
10 1s
11 2s
12 4s
13 8s
14 16s
15 32s
16 64s
17 128s
18 256s
19 512s
20 1024s

Views

100GE interface view, 10G LAN interface view, 25GE interface view, 40GE interface view, 50GE interface view, FlexE-100G interface view, FlexE-400G interface view, FlexE-50G interface view, GE optical interface view, GE electrical interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
clksync	write

Usage Guidelines

Usage Scenario

Two devices exchange Announce packets to determine the master/slave relationship. The master device sends Sync packets to notify the slave device of time signal parameters and uses a delay measurement mechanism to achieve time signals accuracy.

Precautions

If announce-interval is set to a small value, PTP devices frequently exchange PTP messages, occupying many bandwidth resources. If announce-interval is set to a large value, high-precision clock synchronization cannot be guaranteed. Therefore, you are advised to set announce-interval to a large value when the time precision requirement is met.

Timeout interval at which Announce packets are received on the peer interface = Number of timeout times at which Announce packets are received on the peer interface (receipt-timeout) x Interval at which Announce packets are sent on the local interface (announce-interval) x Interval at which Announce packets are sent on the local interface. The number of timeouts for the peer interface to receive Announce packets (receipt-timeout) is configured using the ptp announce receipt-timeout receipt-timeout command.

To ensure that the peer device can correctly receive Announce packets, the interval for sending Announce packets on the local interface must be smaller than the timeout interval for receiving Announce packets on the peer interface. Generally, the interval for sending Announce packets on the local interface is set to 1/4 of the timeout interval for receiving Announce packets on the peer interface. That is, the value of announce-interval is smaller than the value of announce-receipt-timeout by 2.

Example

# Set the interval at which a 1588v2 interface sends Announce packets to 256/1024s.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet 0/1/0
[~HUAWEI-GigabitEthernet0/1/0] ptp announce-interval 8