Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

header-navigation
keyboard_arrow_up
close
keyboard_arrow_left
Timing and Synchronization Guide
Table of Contents Expand all
list Table of Contents
file_download PDF
{ "lLangCode": "en", "lName": "English", "lCountryCode": "us", "transcode": "en_US" }
English
keyboard_arrow_right

Example: Configure PTP Boundary Clock With Unicast Negotiation

date_range 20-Dec-24

This example shows how to configure a boundary clock with unicast negotiation turned on and a mixture of manual, secure and automatic clock clients, which have a timeReceiver relationship to the timeTransmitter boundary clock. The unicast negotiation applies to clock sources, which are configured on the timeReceiver or clock client. Clock clients, configured on the timeTransmitter, are not affected by unicast negotiation.

Note:

ACX5048 and ACX5096 routers do not support boundary clock.

In this example, unicast-negotiation is applicable only to clock-sources. For clock clients, the statement unicast-negotiation at the [edit protocols ptp] hierarchy level is not effective.

Requirements

This example uses the following hardware and software components:

Note:

This example also applies to QFX Series switches. QFX Series switches do not support Gigabit Ethernet interfaces. Instead, configure PTP boundary clock parameters on 10-Gigabit Ethernet interfaces.

  • An ACX Series router

  • Junos OS Release 12.3 or later

Overview

A PTP timeReceiver clock or clock client can join a timeTransmitter clock with and without unicast negotiation. With unicast negotiation, the announce, synchronization, and delay response packet rates are negotiated between the timeTransmitter and the timeReceiver before a PTP session is established. Without unicast negotiation and after it is configured, the timeReceiver or the clock client immediately receives announce and synchronization packets.

A clock client is the remote PTP host, which receives time from the PTP timeTransmitter. The following clock clients are configured in this example:

  • Secure timeReceiver—A secure timeReceiver is configured with an exact IP address, after which, it joins a timeTransmitter clock through unicast negotiation. In this example, the clock client clock-client 117.117.117.117/32 local-ip-address 109.109.109.53 is a secure timeReceiver, which means that only this specific host from the subnet can join the timeTransmitter clock through a unicast negotiation .

  • Automatic timeReceiver—An automatic timeReceiver is configured with an IP address, which includes a subnet mask, indicating that any PTP host belonging to that subnet, can join the timeTransmitter clock through a unicast negotiation. In this example, the clock client clock-client 109.109.109.0/24 local-ip-address 109.109.109.53 is an automatic timeReceiver. Additionally, this automatic timeReceiver is configured on the same timeTransmitter clock interface—109.109.109.53—as the secure timeReceiver.

  • Manual timeReceiver—A manual timeReceiver does not use unicast negotiation to join the timeTransmitter clock. The manual statement overrides the unicast-negotiation statement configured at the [edit protocols ptp] hierarchy level. As soon as you configure a manual timeReceiver, it starts receiving announce and synchronization packets. In this example, the clock client clock-client 7.7.7.7 local-ip-address 7.7.7.53 manual is the manual timeReceiver and is configured on a second timeTransmitter clock interface.

Configuration

A boundary clock must include the configuration of at least one timeTransmitter and at least one timeReceiver. The boundary timeTransmitter receives time from a remote timeTransmitter through the timeReceiver, and in turn passes that time on to clock clients, which are in a timeReceiver relationship to the boundary timeTransmitter. In this example, you configure a boundary timeReceiver, two Precision Time Protocol (PTP) boundary timeTransmitters with three different kinds of clock clients—automatic, manual, and secure. Two of the clock clients are configured on the same boundary timeTransmitter.

Procedure

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them in a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level:

content_copy zoom_out_map
set protocols ptp clock-mode boundary
set protocols ptp unicast-negotiation
set protocols ptp slave interface ge-0/1/0.0 unicast-mode transport ipv4
set protocols ptp slave interface ge-0/1/0.0 unicast-mode clock-source 10.10.10.50 local-ip-address 10.10.10.53
set protocols ptp master interface ge-0/1/3.0 unicast-mode transport ipv4
set protocols ptp master interface ge-0/1/3.0 unicast-mode clock-client 117.117.117.117/32 local-ip-address 109.109.109.53
set protocols ptp master interface ge-0/1/3.0 unicast-mode clock-client 109.109.109.0/24 local-ip-address 109.109.109.53
set protocols ptp master interface ge-0/1/5.0 unicast-mode transport ipv4
 set protocols ptp master interface ge-0/1/5.0 unicast-mode clock-client 7.7.7.7/32 local-ip-address 7.7.7.53 manual

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.

To configure a boundary clock with unicast negotiation:

  1. Configure the clock mode.

    content_copy zoom_out_map
    [edit protocols ptp]
    user@host# set clock-mode boundary
    
  2. Enable unicast negotiation.

    content_copy zoom_out_map
    [edit protocols ptp]
    user@host# set unicast-negotiation
    
  3. Configure the local timeReceiver interface from which the boundary timeTransmitter receives time and passes it on to the configured clock timeReceiver clocks.

    content_copy zoom_out_map
    [edit protocols ptp]
    user@host# edit slave interface ge-0/1/0.0
    
  4. Configure the upstream unicast PTP timeTransmitter clock source parameters.

    content_copy zoom_out_map
    [edit protocols ptp slave interface ge-0/1/0.0]
    user@host# edit unicast-mode
    
  5. Configure the encapsulation type for PTP packet transport.

    content_copy zoom_out_map
    [edit protocols ptp slave interface  ge-0/1/0.0 unicast-mode ]
    user@host# set transport ipv4
    
  6. Configure the PTP timeTransmitter parameters by specifying the IP address of the PTP timeTransmitter clock and the IP address of the local interface.

    content_copy zoom_out_map
    [edit protocols ptp slave interface ge-0/1/0.0 unicast-mode ]
    user@host# set clock-source 10.10.10.50 local-ip-address 10.10.10.53
    
  7. Configure the first timeTransmitter interface in this example.

    content_copy zoom_out_map
    [edit protocols ptp]
    user@host# edit master interface ge-0/1/3.0
    
  8. On the first timeTransmitter interface, configure the downstream PTP clock clients.

    content_copy zoom_out_map
    [edit protocols ptp master interface ge-0/1/3.0 ]
    user@host# edit unicast-mode
    
  9. On the first timeTransmitter interface, configure the encapsulation type for PTP packet transport.

    content_copy zoom_out_map
    [edit protocols ptp master interface ge-0/1/3.0  unicast-mode]
    user@host# set transport ipv4
    
  10. On the first timeTransmitter interface, configure the PTP timeTransmitter parameters by specifying the exact IP address of the remote PTP host and the IP address of the local PTP timeTransmitter interface.

    content_copy zoom_out_map
    [edit protocols ptp master interface ge-0/1/3.0 unicast-mode]
    user@host# set clock-client 117.117.117.117 local-ip-address 109.109.109.53
    
  11. On the first timeTransmitter interface, configure a second PTP timeTransmitter by specifying the IP address and subnet of the second remote PTP host and the IP address of the local PTP timeTransmitter interface.

    content_copy zoom_out_map
    [edit protocols ptp master interface ge-0/1/3.0 unicast-mode]
    user@host# set clock-client 109.109.109.0/24 local-ip-address 109.109.109.53
    
  12. Configure the second timeTransmitter interface with the following parameters: the encapsulation type, the downstream PTP host, the IP address of the local PTP timeTransmitter interface, and the manual statement so that this clock client does not use unicast negotiation.

    content_copy zoom_out_map
    [edit protocols ptp master]
    user@host# set interface ge-0/1/5.0 unicast-mode transport ipv4
    user@host# set interface ge-0/1/5.0 unicast-mode clock-client 7.7.7.7 local-ip-address 7.7.7.53 manual
    

Results

From configuration mode, confirm your configuration by entering the show command. If the output does not display the intended configuration, repeat the configuration instructions in this example to correct it.

content_copy zoom_out_map
[edit protocols ptp]
user@host# show 
clock-mode boundary;
unicast-negotiation;
slave {
    interface ge-0/1/0.0 {
        unicast-mode {
            transport ipv4;
            clock-source 10.10.10.50 local-ip-address 10.10.10.53;
        }
    }
}
master {
    interface ge-0/1/3.0 {
        unicast-mode {
            transport ipv4;
            clock-client 117.117.117.117/32 local-ip-address 109.109.109.53;
            clock-client 109.109.109.0/24 local-ip-address 109.109.109.53;
        }
    }
    interface ge-0/1/5.0 {
        unicast-mode {
            transport ipv4;
            clock-client 7.7.7.7/32 local-ip-address 7.7.7.53 {
                manual;
            }
        }
    }
}

After you have configured the device, enter the commit command from configuration mode.

footer-navigation