Precision Time Protocol (PTP) provides time synchronization among devices with submicrosecond accuracy. It provides also precise frequency synchronization.

Basic concepts

PTP profile

PTP profiles (PTP standards) include:

· IEEE 1588 version 2—1588v2 defines high-accuracy clock synchronization mechanisms. It can be customized, enhanced, or tailored as needed. 1588v2 is the latest version.

· IEEE 802.1AS—802.1AS is introduced based on IEEE 1588. It specifies a profile for use of IEEE 1588-2008 for time synchronization over a virtual bridged local area network (as defined by IEEE 802.1Q). 802.1AS supports only point-to-point full-duplex Ethernet, IEEE 802.11, and IEEE 802.3 EPON links.

· SMPTE ST 2059-2—ST2059-2 is introduced based on IEEE 1588. It specifies a profile specifically for time synchronization of audio or video equipment in a professional broadcast environment. It includes a self-contained description of parameters, their default values, and permitted ranges.

· AES67-2015—AES67-2015 is introduced based on IEEE 1588. It specifies a profile specifically for time synchronization of professional equipment for broadcast, music production, and film and television post-production. It includes a self-contained description of parameters, their default values, and permitted ranges.

PTP domain

A PTP domain refers to a network or part of a network that is enabled with PTP. A PTP domain has only one reference clock called "grandmaster clock (GM)." All devices in the domain synchronize to the clock.

PTP instance

If the device belongs to multiple PTP domains, you must configure and associate a PTP instance with each PTP domain. You can configure PTP settings such as PTP profile and clock node type on a PTP instance. The settings take effect only on the PTP domain associated with the PTP instance. PTP instances are isolated from each other, allowing different PTP timing systems to run on a network without affecting each other.

Optimal PTP domain

Each PTP instance has a reference clock and clock information. For a device that has multiple PTP instances running simultaneously, you must select an optimal PTP instance and use the clock source traced by this PTP instance to synchronize the system time of the device. The domain with which the optimal PTP associates is the optimal domain.

Clock node and PTP port

A node in a PTP domain is a clock node. A port enabled with PTP is a PTP port. PTP defines the following types of basic clock nodes:

· Ordinary Clock (OC)—A PTP clock with a single PTP port in a PTP domain for time synchronization. It synchronizes time from its upstream clock node through the port. If an OC operates as the clock source, it sends synchronization time through a single PTP port to its downstream clock nodes.

· Boundary Clock (BC)—A clock with more than one PTP port in a PTP domain for time synchronization. A BC uses one of the ports to synchronize time from its upstream clock node. It uses the other ports to synchronize time to the relevant upstream clock nodes. If a BC operates as the clock source, such as BC 1 in Figure 1, it synchronizes time through multiple PTP ports to its downstream clock nodes.

· Transparent Clock (TC)—A TC does not keep time consistency with other clock nodes. A TC has multiple PTP ports. It forwards PTP messages among these ports and performs delay corrections for the messages, instead of performing time synchronization. TCs include the following types:

¡ End-to-End Transparent Clock (E2ETC)—Forwards non-P2P PTP packets in the network and calculates the delay of the entire link.

¡ Peer-to-Peer Transparent Clock (P2PTC)—Forwards only Sync, Follow_Up, and Announce messages, terminates other PTP messages, and calculates the delay of each link segment.

IMPORTANT:

When multiple PTP domains are configured on the device, the synchronization performance might fluctuate or decrease, and synchronization failure might occur because of limitation of hardware resources. OC and BC clock nodes do much more work than TCs. As a best practice, configure the device operating in multiple domains as an OC or BC clock node in a maximum of one PTP instance, to decrease calculations, minimize mutual influences between the domains, and optimize the synchronization performance.

Figure 1 shows the positions of these types of clock nodes in a PTP domain.

Figure 1 Clock nodes in a PTP domain

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In addition to these basic types of clock nodes, PTP introduces hybrid clock nodes. For example, a TC+OC has multiple PTP ports in a PTP domain. One port is the OC type, and the others are the TC type.

A TC+OC forwards PTP messages through TC-type ports and performs delay corrections. In addition, it synchronizes time through its OC-type port. TC+OCs include these types: E2ETC+OC and P2PTC+OC.

Master-member/subordinate relationship

The master-member/subordinate relationship is automatically determined based on the Best Master Clock (BMC) algorithm. You can also manually specify a role for the clock nodes.

The master-member/subordinate relationship is defined as follows:

· Master/Member node—A master node sends a synchronization message, and a member node receives the synchronization message.

· Master/Member clock—The clock on a master node is a master clock (parent clock) The clock on a member node is a member clock.

· Master/Subordinate port—A master port sends a synchronization message, and a subordinate port receives the synchronization message. The master and subordinate ports can be on a BC or an OC.

A port that neither receives nor sends synchronization messages is a passive port.

Clock source type

A clock node supports the following clock sources:

· Local clock—38.88 MHz clock signals generated by a crystal oscillator inside the clock monitoring module.

· External clock—Clock signals generated by an external clock device. The signals are received and sent by a 1PPS/ToD port on the device. It is also called a ToD clock source.

Grandmaster clock

As shown in Figure 1, the grandmaster clock (GM) is the ultimate source of time for clock synchronization in a PTP domain. It is elected automatically by the clock nodes in the PTP domain. The clock nodes exchange PTP messages and elect the GM by comparing the clock priority, time class, and time accuracy carried in the PTP messages.

You can also specify a GM manually.

Grandmaster clock selection and master-member/subordinate relationship establishment

A GM can be manually specified. It can also be elected through the BMC algorithm as follows:

1. The clock nodes in a PTP domain exchange announce messages and elect a GM by using the following rules in descending order:

a. Clock node with higher priority 1.

b. Clock node with higher time class.

c. Clock node with higher time accuracy.

d. Clock node with higher priority 2.

e. Clock node with a smaller port ID (containing clock number and port number).

The master nodes, member nodes, master ports, and subordinate ports are determined during the process. Then a spanning tree with the GM as the root is generated for the PTP domain.

2. The master node periodically sends announce messages to the member nodes. If the member nodes do not receive announce messages from the master node, they determine that the master node is invalid, and they start to elect another GM.

Optimal domain selection

If only one PTP instance is configured on the device, this PTP instance is the optimal instance of the device. If multiple PTP instances are configured on the device, the optimal PTP instance (domain) is selected by using the following rules in descending order:

1. Activated instance (with a domain configured).

2. Instance on which the device is an OC or BC clock node.

3. Instance on which the clock source has a higher priority 1 value

4. Instance on which the clock source has a higher time class.

5. Instance on which the clock source has higher time accuracy.

6. Instance on which the clock source has a lower offset from the GM.

7. Instance on which the clock source has a higher priority 2 value.

8. Instance associated with a PTP domain that has a smaller domain ID.

The PTP instance on which the ptp active force-state command is configured has the lowest priority.

Synchronization mechanism

After master-member relationships are established between the clock nodes, the master and member clock nodes exchange PTP messages and record the message transmit and receive time. Based on the timestamps, each member clock calculates the path delay between them and the master clock and adjusts their time accordingly for time synchronization with the master clock.

PTP defines two path delay measurement mechanisms: Request_Response_ and Peer Delay, both of which are based on network symmetry.

Request_Response

The Request_Response mechanism measures the average path delay between the master and member clock nodes by using the Sync, Delay_Req, Delay_Resp, and Follow_Up messages as shown in Figure 2. A TC between master and member clock nodes does not calculate the path delay. It forwards PTP messages and notifies the member clock of the PTP message residence time on it.

This mechanism can be implemented in one of the following two modes:

· Two-step mode—t1 is carried in the Follow_Up message, as shown in Figure 2.

· Single-step mode—t1 is carried in the Sync message, and no Follow_Up message is sent.

Figure 2 shows the Request_Response mechanism in two-step mode.

1. The master clock sends a Sync message to the member clock, and records the sending time t1. Upon receiving the message, the member clock records the receiving time t2.

2. After sending the Sync message, the master clock immediately sends a Follow_Up message that carries time t1.

3. The member clock sends a Delay_Req message to the master clock, and records the sending time t3. Upon receiving the message, the master clock records the receiving time t4.

4. The master clock returns a Delay_Resp message that carries time t4.

After this procedure, the member clock obtains all four timestamps and can make the following calculations:

· Round-trip delay between the master and member clocks: (t2 – t1) + (t4 – t3)

· One-way delay between the master and member clocks: [(t2 – t1) + (t4 – t3)] / 2

· Offset between the member and master clocks: (t2 – t1) – [(t2 – t1) + (t4 – t3)] / 2 or [(t2 – t1) – (t4 – t3)] / 2

Figure 2 Request_Response mechanism (two-step node)

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Peer Delay

The Peer Delay mechanism measures the average path delay between two clock nodes by using Pdelay messages. TCs that exist between master and member clock nodes will divide the synchronization path into multiple links. They calculate the link delays and notify the member clock of the link delays and PTP message residence time on them.

This mechanism can be implemented in one of the following two modes:

· Two-step mode

As shown in Figure 3, Pdelay messages include Pdelay_Req, Pdelay_Resp, and Pdelay_Resp_Follow_Up messages. t2 is carried in the Pdelay_Resp message, and t3 is carried in the Pdelay_Resp_Follow_Up message.

· Single-step mode

Pdelay messages include Pdelay_Req and Pdelay_Resp messages. t3 – t2 is carried in the Pdelay_Resp, and no Pdelay_Resp_Follow_Up message is sent.

The two clock nodes (BC, TC or OC) using this mechanism will send Pdelay messages to each other, and calculate the one-way link delay between them independently. The message interaction process and delay calculation method are identical on the two nodes. Figure 3 uses Clock node B as an example to describe the Peer Delay mechanism.

1. Clock node B sends a Pdelay_Req message to Clock node A, and records the sending time t1. Upon receiving the message, Clock node A records the receiving time t2.

2. Clock node A sends a Pdelay_Req message that carries t2 to Clock node B, and records the sending time t3. Upon receiving the message, Clock node B records the receiving time t4.

3. Clock node A immediately sends a Pdelay_Resp_Follow_Up message carrying t3 to Clock node B after sending the Pdelay_Req message.

After this procedure, Clock node B obtains all four timestamps and can make the following calculations:

· Round-trip delay between Clock node A and Clock node B: (t2 – t1) + (t4 – t3)

· One-way delay between Clock node A and Clock node B: [(t2 – t1) + (t4 – t3)] / 2 = [(t3 – t2) + (t4 – t1)] / 2

· Time offset between the member clock and the master clock: Sync message receiving time on the member clock – Sync message sending time on the master clock – Total one-way delays on all links – Total PTP message residence time on all TCs.

Figure 3 Peer Delay mechanism (two-step mode)

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Protocols and standards

· IEEE Std 1588-2008, IEEE Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems, 2008

· IEEE 802.1AS, Timing and Synchronization for Time-Sensitive Applications in Bridged Local Area Networks

· SMPTE ST 2059-2, SMPTE Profile for Use of IEEE-1588 Precision Time Protocol in Professional Broadcast Applications

· AES67-2015, AES Standard for Audio Applications of Networks-High-Performance Streaming Audio-Over-IP Interoperability, 2015

Restrictions and guidelines: PTP configuration

Before configuring PTP, determine the PTP profile and define the scope of the PTP domain and the role of every clock node.

Only the default MDC supports PTP. Non-default MDCs do not support PTP or PTP commands. For more information about MDCs, see Virtual Technologies Configuration Guide.

PTP tasks at a glance

Configuring PTP (IEEE 1588 version 2)

1. Specifying PTP for obtaining the time

2. (Optional.) Creating a PTP instance

3. Specifying a PTP profile

Specify the IEEE 1588 version 2 PTP profile.

4. Configuring clock nodes

¡ Specifying a clock node type

¡ (Optional.) Configuring an OC to operate only as a member clock

5. (Optional.) Specifying a PTP domain

6. Enabling PTP on a port

7. Configuring PTP ports

¡ (Optional.) Configuring the role of a PTP port

¡ Configuring the mode for carrying timestamps

¡ Specifying a delay measurement mechanism for a BC or an OC

¡ Configuring one of the ports on a TC+OC clock as an OC-type port

8. (Optional.) Configuring PTP message transmission and receipt

¡ Setting the interval for sending announce messages and the timeout multiplier for receiving announce messages

¡ Setting the interval for sending Pdelay_Req messages

¡ Setting the interval for sending Sync messages

¡ Setting the minimum interval for sending Delay_Req messages

9. (Optional.) Configuring parameters for PTP messages

¡ Specifying

¡ Configuring a source IP address for multicast PTP messages transported over IPv4 UDP

¡ Configuring a destination IP address for unicast PTP messages transported over IPv4 UDP

¡ Configuring the MAC address for non-Pdelay messages

¡ Setting a DSCP value for PTP messages transmitted over UDP

¡ Specifying a VLAN tag for PTP messages

10. (Optional.) Adjusting and correcting clock synchronization

¡ Setting the delay correction value

¡ Setting the cumulative offset between UTC and TAI

¡ Setting the correction date of the UTC

11. (Optional.) Configuring a priority for a clock

Configuring PTP (IEEE 802.1AS)

1. Specifying PTP for obtaining the time

2. (Optional.) Creating a PTP instance

3. Specifying a PTP profile

Specify the IEEE 802.1AS PTP profile.

4. Configuring clock nodes

¡ Specifying a clock node type

¡ (Optional.) Configuring an OC to operate only as a member clock

5. (Optional.) Specifying a PTP domain

6. Enabling PTP on a port

7. Configuring PTP ports

¡ (Optional.) Configuring the role of a PTP port

¡ Configuring one of the ports on a TC+OC clock as an OC-type port

8. (Optional.) Configuring PTP message transmission and receipt

¡ Setting the interval for sending announce messages and the timeout multiplier for receiving announce messages

¡ Setting the interval for sending Pdelay_Req messages

¡ Setting the interval for sending Sync messages

9. (Optional.) Specifying a VLAN tag for PTP messages

10. (Optional. ) Adjusting and correcting clock synchronization

¡ Setting the delay correction value

¡ Setting the cumulative offset between UTC and TAI

¡ Setting the correction date of the UTC

11. (Optional.) Configuring a priority for a clock

Configuring PTP (SMPTE ST 2059-2)

1. Specifying PTP for obtaining the time

2. (Optional.) Creating a PTP instance

3. Specifying a PTP profile

Specify the SMPTE ST 2059-2 PTP profile.

4. Configuring clock nodes

¡ Specifying a clock node type

¡ (Optional.) Configuring an OC to operate only as a member clock

5. (Optional.) Specifying a PTP domain

6. Enabling PTP on a port

7. Configuring PTP ports

¡ (Optional.) Configuring the role of a PTP port

¡ Configuring the mode for carrying timestamps

¡ Specifying a delay measurement mechanism for a BC or an OC

8. (Optional.) Configuring PTP message transmission and receipt

¡ Setting the interval for sending announce messages and the timeout multiplier for receiving announce messages

¡ Setting the interval for sending Pdelay_Req messages

¡ Setting the interval for sending Sync messages

¡ Setting the minimum interval for sending Delay_Req messages

9. (Optional.) Configuring parameters for PTP messages

¡ Configuring a source IP address for multicast PTP messages transported over IPv4 UDP

¡ Configuring a destination IP address for unicast PTP messages transported over IPv4 UDP

¡ Setting a DSCP value for PTP messages transmitted over UDP

¡ Specifying a VLAN tag for PTP messages

10. (Optional.) Adjusting and correcting clock synchronization

¡ Setting the delay correction value

¡ Setting the cumulative offset between UTC and TAI

¡ Setting the correction date of the UTC

11. (Optional.) Configuring a priority for a clock

Configuring PTP (AES67-2015)

1. Specifying PTP for obtaining the time

2. (Optional.) Creating a PTP instance

3. Specifying a PTP profile

Specify the AES67-2015 PTP profile.

4. Configuring clock nodes

¡ Specifying a clock node type

¡ (Optional.) Configuring an OC to operate only as a member clock

5. (Optional.) Specifying a PTP domain

6. Enabling PTP on a port

7. Configuring PTP ports

¡ (Optional.) Configuring the role of a PTP port

¡ Configuring the mode for carrying timestamps

¡ Specifying a delay measurement mechanism for a BC or an OC

¡ Configuring one of the ports on a TC+OC clock as an OC-type port

8. (Optional.) Configuring PTP message transmission and receipt

¡ Setting the interval for sending announce messages and the timeout multiplier for receiving announce messages

¡ Setting the interval for sending Pdelay_Req messages

¡ Setting the interval for sending Sync messages

¡ Setting the minimum interval for sending Delay_Req messages

9. (Optional.) Configuring parameters for PTP messages

¡ Configuring a source IP address for multicast PTP messages transported over IPv4 UDP

¡ Configuring a destination IP address for unicast PTP messages transported over IPv4 UDP

¡ Setting a DSCP value for PTP messages transmitted over UDP

¡ Specifying a VLAN tag for PTP messages

10. (Optional.) Adjusting and correcting clock synchronization

¡ Setting the delay correction value

¡ Setting the cumulative offset between UTC and TAI

¡ Setting the correction date of the UTC

11. (Optional.) Configuring a priority for a clock

Specifying PTP for obtaining the time

1. Enter system view.

system-view

2. Specify PTP for obtaining the time.

clock protocol ptp mdc 1

By default, the device uses NTP to synchronize the system time.

The device supports PTP configuration only on the default MDC. You must specify the default MDC for this command to take effect. The ID of the default MDC is 1.

For more information about the clock protocol command, see device management commands in Fundamentals Command Reference.

Creating a PTP instance

About this task

A PTP instance is uniquely identified by its ID on a device. For easy identification and management, you can also set a name for a PTP instance.

Restrictions and guidelines

Do not set the same name for different PTP instances.

If you create PTP instances with the same ID but different names, the most recent configuration takes effect.

The default PTP instance with an ID of 0 has been created by default. You cannot delete the default PTP instance. PTP settings configured in system view take effect only on PTP instance 0. To configure settings for a PTP instance other than PTP instance 0, enter PTP instance view.

Procedure

1. Enter system view.

system-view

2. Create a PTP instance.

ptp instance ptp-instance-id [ name ptp-instance-name ]

By default, PTP instance numbered 0 and named default-instance exists.

Specifying a PTP profile

Restrictions and guidelines

You must specify a PTP profile before configuring PTP settings. Changing the PTP profile clears all settings under the profile.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Specify a PTP profile.

ptp profile { 1588v2 | 8021as | aes67-2015 | st2059-2 }

By default, no PTP profile is configured, and PTP is not running on the device.

Configuring clock nodes

Specifying a clock node type

Restrictions and guidelines

You can specify only one clock node type for the device. The clock node types include OC, BC, E2ETC, P2PTC, E2ETC+OC, and P2PTC+OC.

Before you specify a clock node type, specify a PTP profile.

For the IEEE 802.1AS PTP profile, you cannot specify the E2ETC or E2ETC+OC clock node type.

For the SMPTE ST 2059-2 or AES67-2015 PTP profile, you cannot specify the E2ETC+OC or P2PTC+OC clock node type.

Changing or removing the clock node type restores the default settings of the PTP profile.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Specify a clock node type for the device.

ptp mode { bc | e2etc | e2etc-oc | oc | p2ptc | p2ptc-oc }

By default, no clock node type is specified.

Configuring an OC to operate only as a member clock

About this task

An OC can operate either as a master clock to send synchronization messages or as a member clock to receive synchronization messages. This task allows you to configure an OC to operate only as a member clock.

If an OC is operating only as a member clock, you can use the ptp force-state command to configure its PTP port as a master port or passive port.

Restrictions and guidelines

This task is applicable only to OCs.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Configure the OC to operate only as a member clock.

ptp slave-only

By default, an OC operates as a master or member clock.

Specifying a PTP domain

About this task

Within a PTP domain, all devices follow the same rules to communicate with each other. Devices in different PTP domains cannot exchange PTP messages.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Specify a PTP domain for the device.

ptp domain value

By default, no PTP domain exists.

Do not configure the same domain on different PTP instances.

Enabling PTP on a port

About this task

For PTP to run on a port, enable PTP on it.

Restrictions and guidelines

You can enable PTP on only one port on an OC.

To enable PTP on a Layer 2 Ethernet interface, make sure the VLAN interface for the VLAN to which the Layer 2 interface belongs is not associated with any VPN instance (the ip binding command not configured on the VLAN interface).

To enable PTP on a Layer 3 Ethernet interface that has been assigned to a VPN instance, you must specify this VPN instance in the ptp source ip-address vpn-instance vpn-instance-name command if PTP messages are to be transmitted in multicast mode over IPv4 UDP.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Enable PTP on the port.

ptp enable

By default, PTP is disabled on a port.

Configuring PTP ports

Configuring the role of a PTP port

About this task

You can configure the master, passive, or slave role for a PTP port.

For an OC that operates in slave-only mode, you can perform this task to change its PTP port role to master or slave.

Restrictions and guidelines

By default, the PTP port roles are automatically negotiated based on the BMC algorithm. If you use the ptp force-state command to change the role of one PTP port, all the other PTP ports in the PTP domain stop working. For these PTP ports to function, you must specify roles for each of them by using the ptp force-state command. As a best practice, enable automatic negotiation of PTP port roles based on the BMC algorithm.

You can configure only one subordinate port for the device.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Configure the role of the PTP port.

ptp force-state { master | passive | slave }

By default, the PTP port role is automatically calculated through BMC.

5. Return to system view.

quit

6. (Optional.) Enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

7. Activate the port role configuration.

ptp active force-state

By default, the port role configuration is not activated.

Configuring the mode for carrying timestamps

‌About this task

Timestamps can be carried in either of the following modes:

· Single-step mode—The following messages contain the message sending time:

¡ Sync message in the Request_Response and Peer Delay mechanisms.

¡ Pdelay_Resp message in the Peer Delay mechanism.

· Two-step mode—All messages contain the message sending time, except for the following messages:

¡ Sync message in the Request_Response and Peer Delay mechanisms.

¡ Pdelay_Resp message in the Peer Delay mechanism.

Restrictions and guidelines

The IEEE 802.1AS PTP profile supports only the two-step mode.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Configure the mode for carrying timestamps.

ptp clock-step { one-step | two-step }

By default, the two-step mode is used for carrying timestamps.

Specifying a delay measurement mechanism for a BC or an OC

About this task

PTP defines two transmission delay measurement mechanisms: Request_Response and Peer Delay. For correct communication, ports on the same link must share the same delay measurement mechanism.

The delay measurement mechanism is Request_Response for E2ETCs and E2ETC+OCs and Peer Delay for P2PTCs and P2PTC+OCs. You cannot change the delay measurement mechanism for these clock nodes

Restrictions and guidelines

This task is applicable only to BCs and OCs.

The IEEE 802.1AS PTP profile supports only the peer delay measurement mechanism. This task is not available for the IEEE 802.1AS PTP profile.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Specify a delay measurement mechanism for a BC or an OC.

ptp delay-mechanism { e2e | p2p }

The default delay measurement mechanism depends on the PTP profile.

Configuring one of the ports on a TC+OC clock as an OC-type port

About this task

All ports on a TC+OC (E2ETC+OC or P2PTC+OC) are TC-type ports by default. This feature allows you to configure one of the ports on a TC+OC clock as an OC-type port.

Restrictions and guidelines

This task is applicable only to E2ETC+OCs and P2PTC+OCs.

This task is not available for the SMPTE ST 2059-2 or AES67-2015 PTP profile.

For time synchronization accuracy, the OC-type port on an E2ETC+OC or P2PTC+OC must be specified as the master port.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Configure the port type as OC.

ptp port-mode oc

By default, the port type for all ports on a TC+OC is TC.

Configuring PTP message transmission and receipt

Setting the interval for sending announce messages and the timeout multiplier for receiving announce messages

About this task

A master node sends announce messages to the member nodes at the specified interval. If a member node does not receive any announce messages from the master node within the specified interval, it determines that the master node is invalid.

For the IEEE 1588 version 2, AES67-2015, or SMPTE ST 2059-2 PTP profile, the timeout for receiving announce messages is the announce message sending interval for the subordinate node × multiple-value. For IEEE 802.1AS, the timeout for receiving announce messages is the announce message sending interval for the master node × multiple-value.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Set the interval for sending announce messages.

ptp announce-interval interval

The default settings vary by PTP profile.

¡ IEEE 1588 version 2 or AES67-2015—The interval argument value is 1 and the interval for sending announce messages is 2 (21) seconds.

¡ IEEE 802.1AS—The interval argument value is 0 and the interval for sending announce messages is 1 (20)second.

¡ SMPTE ST 2059-2—The interval argument value is –2 and the interval for sending announce messages is 1/4 (2-2) seconds.

5. Set the number of intervals before a timeout occurs.

ptp announce-timeout multiple-value

By default, a timeout occurs when three intervals are reached.

Setting the interval for sending Pdelay_Req messages

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Set the interval for sending Pdelay_Req messages.

ptp pdelay-req-interval interval

By default, the interval argument value is 0 and the interval for sending peer delay request messages is 1 (20) second.

For the SMPTE ST 2059-2 or AES67-2015 PTP profile, set the interval argument to a value in the range of ptp syn-interval interval to ptp syn-interval interval plus 5 as a best practice.

Setting the interval for sending Sync messages

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Set the interval for sending Sync messages.

ptp syn-interval interval

The default settings vary by PTP profile.

¡ IEEE 1588 version 2—The interval argument value is 0 and the interval for sending Sync messages is 1 (20) second.

¡ IEEE 802.1AS, AES67-2015, or SMPTE ST 2059-2—The interval argument value is –3 and the interval for sending Sync messages is 1/8 (2-3) seconds.

Setting the minimum interval for sending Delay_Req messages

About this task

When receiving a Sync or Follow_Up message, an interface can send Delay_Req messages only when the minimum interval is reached. This task allows you to set the minimum interval for sending Delay_Req messages.

Restrictions and guidelines

This setting is not available for the IEEE 802.1AS PTP profile.

In PTP multicast transport mode, this setting takes effect only when configured on the master clock. The master clock sends the value to a member clock through PTP messages to control the interval for the member clock to send Delay_Req messages. To view the interval, execute the display ptp interface command on the member clock.

In PTP unicast transport mode, this setting takes effect when configured on member clocks. It does not take effect when configured on the master clock.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Set the minimum interval for sending Delay_Req messages.

ptp min-delayreq-interval interval

The interval argument value is 0 and the minimum interval for sending delay request messages is 1 (20) second.

For the SMPTE ST 2059-2 PTP profile, set the interval argument to a value in the range of ptp syn-interval interval to ptp syn-interval interval plus 5 as a best practice.

Configuring parameters for PTP messages

Specifying the IPv4 UDP transport protocol for PTP messages

About this task

PTP messages can be encapsulated in IEEE 802.3/Ethernet packets or UDP packets.

Restrictions and guidelines

The IEEE 802.1AS PTP profile supports only IEEE 802.3/Ethernet transport of PTP messages and does not support this task.

The SMPTE ST 2059-2 or AES67-2015 PTP profile supports only UDP transport of PTP messages and does not support this task.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Configure the IPv4 UDP transport protocol for PTP messages.

ptp transport-protocol udp

By default, PTP messages are encapsulated in IEEE 802.3/Ethernet packets.

Configuring a source IP address for multicast PTP messages transported over IPv4 UDP

About this task

To transport multicast PTP messages over IPv4 UDP, you must configure a source IP address for the messages.

Restrictions and guidelines

If both a source IP address for multicast PTP messages transported over IPv4 UDP and a destination address for unicast PTP messages transported over IPv4 UDP are configured, the system unicasts the messages.

This task is not available for the IEEE 802.1AS PTP profile.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Configure a source IP address for multicast PTP messages transported over IPv4 UDP.

ptp source ip-address [ vpn-instance vpn-instance-name ]

By default, no source IP address is configured for multicast PTP messages transported over IPv4 UDP.

Configuring a destination IP address for unicast PTP messages transported over IPv4 UDP

About this task

To transport unicast PTP messages over IPv4 UDP, you must configure a destination IP address for the messages.

Restrictions and guidelines

This task is not available for the IEEE 802.1AS PTP profile.

Prerequisites

Configure an IP address for the current interface, and make sure the interface and the peer PTP interface can reach each other.

Procedure

1. Enter system view.

system-view

2. Enter Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Configure a destination IP address for unicast PTP messages transported over IPv4 UDP.

ptp unicast-destination ip-address

By default, no destination IP address is configured for unicast PTP messages transported over IPv4 UDP.

Configuring the MAC address for non-Pdelay messages

About this task

Pdelay messages include Pdelay_Req, Pdelay_Resp, and Pdelay_Resp_Follow_Up messages. The destination MAC address of Pdelay messages is 0180-C200-000E by default, which cannot be modified. The destination MAC address of non-Pdelay messages is either 0180-C200-000E or 011B-1900-0000.

Restrictions and guidelines

This feature takes effect only when PTP messages are encapsulated in IEEE 802.3/Ethernet packets.

This task is not available for the IEEE 802.1AS, SMPTE ST 2059-2, or AES67-2015 PTP profile.

Procedure

1. Enter system view.

system-view

2. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

4. Configure the destination MAC address for non-Pdelay messages.

ptp destination-mac mac-address

The default destination MAC address is 011B-1900-0000.

Setting a DSCP value for PTP messages transmitted over UDP

About this task

The DSCP value determines the sending precedence of PTP messages transmitted over UDP.

Restrictions and guidelines

This task is not available for the IEEE 802.1AS PTP profile.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Set a DSCP value for PTP messages transmitted over IPv4 UDP.

ptp dscp dscp

By default, the DSCP value is 56.

Specifying a VLAN tag for PTP messages

About this task

Perform this task to configure the VLAN ID and the 802.1p precedence in the VLAN tag carried by PTP messages.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Specify a VLAN tag for PTP messages.

ptp vlan vlan-id [ dot1p dot1p-value ]

By default, PTP messages do not have a VLAN tag.

Adjusting and correcting clock synchronization

Setting the delay correction value

About this task

PTP performs time synchronization based on the assumption that the delays in sending and receiving messages are the same. However, this is not practical. If you know the offset between the delays in sending and receiving messages, you can set the delay correction value for more accurate time synchronization.

Procedure

1. Enter system view.

system-view

2. Enter Layer 2 Ethernet interface view or Layer 3 Ethernet interface view.

interface interface-type interface-number

3. (Optional.) Assign the interface to a PTP instance and enter interface PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

4. Set a delay correction value.

ptp asymmetry-correction { minus | plus } value

The default is 0 nanoseconds. Delay correction is not performed.

Setting the cumulative offset between UTC and TAI

About this task

An offset exists between Coordinated Universal Time (UTC) and International Atomic Time (TAI). The device displays the UTC time. However, PTP uses TAI for time synchronization. For the device to synchronize correct time to other clock nodes in the PTP domain when its local clock is selected as the GM, configure this command to correct the offset between UTC and TAI.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Set the cumulative offset between UTC and TAI.

ptp utc offset utc-offset

The default is 0 seconds.

Setting the correction date of the UTC

About this task

This task allows you to adjust the UTC at the last minute (23:59) of the specified date.

Restrictions and guidelines

If you configure the setting multiple times, the most recent configuration takes effect.

This setting takes effect only when it is configured on the master clock node and the local clock of the master clock node is the GM.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Set the correction date of the UTC.

ptp utc { leap59-date | leap61-date } date

By default, the correction date of the UTC is not configured.

Configuring a priority for a clock

About this task

Priorities for clocks are used to elect the GM. The smaller the priority value, the higher the priority.

Procedure

1. Enter system view.

system-view

2. (Optional.) Enter PTP instance view.

ptp instance ptp-instance-id

To configure settings for PTP instance 0, skip this step.

3. Configure the priority for the specified clock for GM election through BMC.

ptp priority clock-source local { priority1 priority1 | priority2 priority2 }

The default value varies by PTP profile:

¡ IEEE 1588 version 2, SMPTE ST 2059-2, or AES67-2015—The priority 1 and priority 2 values are both 128.

¡ IEEE 802.1AS—The priority 1 value is 246 and the priority 2 value is 248.

Display and maintenance commands for PTP

Execute display commands in any view and the reset command in user view.

Task	Command
Display PTP clock information.	display ptp clock [ all \| instance ptp-instance-id ]
Display the delay correction history.	display ptp corrections [ all \| instance ptp-instance-id ]
Display information about foreign master nodes.	display ptp foreign-masters-record [ interface interface-type interface-number ] [ all \| instance ptp-instance-id ]
Display PTP information on an interface.	display ptp interface [ interface-type interface-number ] [ all \| instance ptp-instance-id ]
Display brief PTP information on all interfaces.	display ptp interface brief
Display parent node information for the PTP device.	display ptp parent [ all \| instance ptp-instance-id ]
Display PTP statistics.	display ptp statistics [ interface interface-type interface-number ] [ all \| instance ptp-instance-id ]
Display PTP clock time properties.	display ptp time-property [ all \| instance ptp-instance-id ]
Clear PTP statistics.	reset ptp statistics [ interface interface-type interface-number ] [ all \| instance ptp-instance-id ]

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PTP configuration examples

Example: Configuring PTP (IEEE 1588 version 2, IEEE 802.3/Ethernet encapsulation, multicast transmission)

Network configuration

As shown in Figure 4, a PTP domain contains Device A, Device B, and Device C.

· Configure all devices to use the IEEE 1588 version 2 PTP profile.

· Configure PTP messages to be encapsulated in IEEE 802.3/Ethernet packets.

· Specify the OC clock node type for Device A and Device C, and E2ETC clock node type for Device B. The clock nodes elect a GM through BMC.

· Use the default Request_Response delay measurement mechanism on Device A and Device C.

Figure 4 Network diagram

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Procedure

1. Configure Device A:

# Specify the IEEE 1588 version 2 PTP profile.

<DeviceA> system-view

[DeviceA] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceA] ptp mode oc

# Create a PTP domain.

[DeviceA] ptp domain 0

# Specify PTP for obtaining the time on the default MDC.

[DeviceA] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1.

[DeviceA] interface hundredgige 3/0/1

[DeviceA-HundredGigE3/0/1] ptp enable

[DeviceA-HundredGigE3/0/1] quit

2. Configure Device B:

# Specify the IEEE 1588 version 2 PTP profile.

<DeviceB> system-view

[DeviceB] ptp profile 1588v2

# Specify the E2ETC clock node type.

[DeviceB] ptp mode e2etc

# Create a PTP domain.

[DeviceB] ptp domain 0

# Specify PTP for obtaining the time on the default MDC.

[DeviceB] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1.

[DeviceB] interface hundredgige 3/0/1

[DeviceB-HundredGigE3/0/1] ptp enable

[DeviceB-HundredGigE3/0/1] quit

# Enable PTP on HundredGigE 3/0/2.

[DeviceB] interface hundredgige 3/0/2

[DeviceB-HundredGigE3/0/2] ptp enable

[DeviceB-HundredGigE3/0/2] quit

3. Configure Device C:

# Specify the IEEE 1588 version 2 PTP profile.

<DeviceC> system-view

[DeviceC] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceC] ptp mode oc

# Create a PTP domain.

[DeviceC] ptp domain 0

# Specify PTP for obtaining the time on the default MDC.

[DeviceC] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1.

[DeviceC] interface hundredgige 3/0/1

[DeviceC-HundredGigE3/0/1] ptp enable

[DeviceC-HundredGigE3/0/1] quit

Verifying the configuration

When the network is stable, perform the following tasks to verify that Device A is elected as the GM, HundredGigE3/0/1 on Device A is the master port, and Device B has synchronized to Device A:

· Use the display ptp clock command to display PTP clock information.

· Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information on Device A.

[DeviceA] display ptp clock

PTP profile : IEEE 1588 Version 2

PTP mode : OC

Slave only : No

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 0

Number of PTP ports : 1

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 0 (ns)

Mean path delay : 0 (ns)

Steps removed : 0

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device A.

[DeviceA] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 Master E2E Two 0

# Display PTP clock information on Device B.

[DeviceB] display ptp clock

PTP profile : IEEE 1588 Version 2

PTP mode : E2ETC

Slave only : No

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 0

Number of PTP ports : 2

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 106821530000 (ns)

Mean path delay : 2801000 (ns)

Steps removed : 1

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 N/A E2E Two 0

HGE3/0/2 0 N/A E2E Two 0

Example: Configuring PTP (IEEE 1588 version 2, IPv4 UDP encapsulation, multicast transmission)

Network configuration

As shown in Figure 5, a PTP domain contains Device A, Device B, and Device C.

· Configure all devices to use the IEEE 1588 version 2 PTP profile.

· Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

· Specify the OC clock node type for Device A and Device C, and the P2PTC clock node type for Device B. All clock nodes elect a GM through BMC based on their respective default GM attributes.

· Specify the peer delay measurement mechanism (p2p) for Device A and Device C.

Figure 5 Network diagram

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Procedure

1. Configure Device A:

# Specify the IEEE 1588 version 2 PTP profile.

<DeviceA> system-view

[DeviceA] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceA] ptp mode oc

# Create a PTP domain.

[DeviceA] ptp domain 0

# Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceA] ptp source 10.10.1.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceA] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify IPv4 UDP transport of PTP messages, specify the delay measurement mechanism as p2p, and enable PTP.

[DeviceA] interface hundredgige 3/0/1

[DeviceA-HundredGigE3/0/1] ptp transport-protocol udp [DeviceA-HundredGigE3/0/1] ptp delay-mechanism p2p

[DeviceA-HundredGigE3/0/1] ptp enable

[DeviceA-HundredGigE3/0/1] quit

2. Configure Device B:

# Specify the IEEE 1588 version 2 PTP profile.

<DeviceB> system-view

[DeviceB] ptp profile 1588v2

# Specify the P2PTC clock node type.

[DeviceB] ptp mode p2ptc

# Create a PTP domain.

[DeviceB] ptp domain 0

# Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceB] ptp source 10.10.2.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceB] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify IPv4 UDP transport of PTP messages and enable PTP.

[DeviceB] interface hundredgige 3/0/1

DeviceB-HundredGigE3/0/1] ptp transport-protocol udp

[DeviceB-HundredGigE3/0/1] ptp enable

[DeviceB-HundredGigE3/0/1] quit

# On HundredGigE 3/0/2, specify IPv4 UDP transport of PTP messages and enable PTP.

[DeviceB] interface hundredgige 3/0/2

[DeviceB-HundredGigE3/0/2] ptp transport-protocol udp

[DeviceB-HundredGigE3/0/2] ptp enable

[DeviceB-HundredGigE3/0/2] quit

3. Configure Device C:

# Specify the IEEE 1588 version 2 PTP profile.

<DeviceC> system-view

[DeviceC] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceC] ptp mode oc

# Create a PTP domain.

[DeviceC] ptp domain 0

# Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceC] ptp source 10.10.3.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceC] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify IPv4 UDP transport of PTP messages, specify the delay measurement mechanism as p2p, and enable PTP.

[DeviceC] interface hundredgige 3/0/1

[DeviceC-HundredGigE3/0/1] ptp transport-protocol udp [DeviceC-HundredGigE3/0/1] ptp delay-mechanism p2p

[DeviceC-HundredGigE3/0/1] ptp enable

[DeviceC-HundredGigE3/0/1] quit

Verifying the configuration

When the network is stable, perform the following tasks to verify that Device A is elected as the GM, HundredGigE3/0/1 on Device A is the master port, and Device B has synchronized to Device A:

· Use the display ptp clock command to display PTP clock information.

· Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information on Device A.

[DeviceA] display ptp clock

PTP profile : IEEE 1588 Version 2

PTP mode : OC

Slave only : No

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 0

Number of PTP ports : 1

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 0 (ns)

Mean path delay : 0 (ns)

Steps removed : 0

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device A.

[DeviceA] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 Master P2P Two 0

# Display PTP clock information on Device B.

[DeviceB] display ptp clock

PTP profile : IEEE 1588 Version 2

PTP mode : P2PTC

Slave only : No

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 0

Number of PTP ports : 2

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 106368000000 (ns)

Mean path delay : 2700000 (ns)

Steps removed : 1

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 N/A P2P Two 0

HGE3/0/2 0 N/A P2P Two 0

Example: Configuring multiple PTP instances (IEEE 1588 version 2, multicast transmission)

Network configuration

As shown in Figure 6, configure two PTP instances on a PTP network.

· PTP instance 1: Assign Device A, Device B, and Device C to PTP instance 1.

¡ Specify the IEEE 1588 version 2 PTP profile and IEEE 802.3/Ethernet encapsulation of PTP messages for the devices and assign the devices to PTP domain 1.

¡ Specify the OC clock node type for Device A and Device C and E2ETC clock node type for Device B. All these clock nodes elect a GM through BMC.

¡ All clock nodes use the default Request_Response delay measurement mechanism.

· PTP instance 2: Assign Device D, Device B, and Device E to PTP instance 2.

¡ Specify the IEEE 1588 version 2 PTP profile and IPv4 UDP encapsulation of PTP messages for the devices and assign the devices to PTP domain 2.

¡ Specify the OC clock node type for Device D and Device E and P2PTC clock node type for Device B. All the clock nodes elect a GM through BMC.

¡ Specify the peer delay measurement mechanism for all devices.

Figure 6 Network diagram

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Procedure

1. Configure PTP instance 1 (IEEE 802.3/Ethernet encapsulation of PTP messages)

a. Configure Device A:

# Create a PTP instance, specifying its ID as 1 and name as ptp1, and enter its view.

<DeviceA> system-view

[DeviceA] ptp instance 1 name ptp1

# Specify the IEEE 1588 version 2 PTP profile.

[DeviceA-ptp-instance-1] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceA-ptp-instance-1] ptp mode oc

# Specify PTP domain 1.

[DeviceA-ptp-instance-1] ptp domain 1

[DeviceA-ptp-instance-1] quit

# Specify PTP for obtaining the time on the default MDC.

[DeviceA] clock protocol ptp mdc 1

# Assign HundredGigE 3/0/1 to PTP instance 1, enter interface PTP instance view, and enable PTP.

[DeviceA] interface hundredgige 3/0/1

[DeviceA-HundredGigE3/0/1] ptp instance 1

[DeviceA-HundredGigE3/0/1-ptp-instance-1] ptp enable

[DeviceA-HundredGigE3/0/1-ptp-instance-1] quit

[DeviceA-HundredGigE3/0/1] quit

b. Configure Device B:

# Create a PTP instance, specifying its ID as 1 and name as ptp1, and enter its view.

<DeviceB> system-view

[DeviceB] ptp instance 1 name ptp1

# Specify the IEEE 1588 version 2 PTP profile.

[DeviceB-ptp-instance-1] ptp profile 1588v2

# Specify the E2ETC clock node type.

[DeviceB-ptp-instance-1] ptp mode e2etc

# Specify PTP domain 1.

[DeviceB-ptp-instance-1] ptp domain 1

[DeviceB-ptp-instance-1] quit

# Specify PTP for obtaining the time on the default MDC.

[DeviceB] clock protocol ptp mdc 1

# Assign HundredGigE 3/0/1 to PTP instance 1, enter interface PTP instance view, and enable PTP.

[DeviceB] interface hundredgige 3/0/1

[DeviceB-HundredGigE3/0/1] ptp instance 1

[DeviceB-HundredGigE3/0/1-ptp-instance-1] ptp enable

[DeviceB-HundredGigE3/0/1-ptp-instance-1] quit

[DeviceB-HundredGigE3/0/1] quit

# Assign HundredGigE 3/0/2 to PTP instance 1, enter interface PTP instance view, and enable PTP.

[DeviceB] interface hundredgige 3/0/2

[DeviceB-HundredGigE3/0/2] ptp instance 1

[DeviceB-HundredGigE3/0/2-ptp-instance-1] ptp enable

[DeviceB-HundredGigE3/0/2-ptp-instance-1] quit

[DeviceB-HundredGigE3/0/2] quit

c. Configure Device C:

# Create a PTP instance, specifying its ID as 1 and name as ptp1, and enter its view.

<DeviceC> system-view

[DeviceC] ptp instance 1 name ptp1

[DeviceC-ptp-instance-1]

# Specify the IEEE 1588 version 2 PTP profile.

[DeviceC-ptp-instance-1] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceC-ptp-instance-1] ptp mode oc

# Specify PTP domain 1.

[DeviceC-ptp-instance-1] ptp domain 1

[DeviceC-ptp-instance-1] quit

# Specify PTP for obtaining the time on the default MDC.

[DeviceC] clock protocol ptp mdc 1

# Assign HundredGigE 3/0/1 to PTP instance 1, enter interface PTP instance view, and enable PTP.

[DeviceC] interface hundredgige 3/0/1

[DeviceC-HundredGigE3/0/1] ptp instance 1

[DeviceC-HundredGigE3/0/1-ptp-instance-1] ptp enable

[DeviceC-HundredGigE3/0/1-ptp-instance-1] quit

[DeviceC-HundredGigE3/0/1] quit

2. Configure PTP instance 2 (IPv4 UDP encapsulation of PTP messages)

a. Configure Device D:

# Create a PTP instance, specifying its ID as 2 and name as ptp2, and enter its view.

<DeviceD> system-view

[DeviceD] ptp instance 2 name ptp2

# Specify the IEEE 1588 version 2 PTP profile.

[DeviceD-ptp-instance-2] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceD-ptp-instance-1] ptp mode oc

# Specify PTP domain 2.

[DeviceD-ptp-instance-2] ptp domain 2

# Specify the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceD-ptp-instance-2] ptp source 10.10.1.1

[DeviceD-ptp-instance-2] quit

# Specify PTP for obtaining the time on the default MDC.

[DeviceD] clock protocol ptp mdc 1

# Assign HundredGigE3/0/1 to PTP instance 2 and enter interface PTP instance view. Specify IPv4 UDP encapsulation of PTP messages and the peer delay measurement mechanism and enable PTP.

[DeviceD] interface hundredgige 3/0/1

[DeviceD-HundredGigE3/0/1] ptp instance 2

[DeviceD-HundredGigE3/0/1-ptp-instance-2] ptp transport-protocol udp

[DeviceD-HundredGigE3/0/1-ptp-instance-2] ptp delay-mechanism p2p

[DeviceD-HundredGigE3/0/1-ptp-instance-2] ptp enable

[DeviceD-HundredGigE3/0/1-ptp-instance-2] quit

[DeviceD-HundredGigE3/0/1] quit

b. Configure Device B:

# Create a PTP instance, specifying its ID as 2 and name as ptp2, and enter its view.

<DeviceB> system-view

[DeviceB] ptp instance 2 name ptp2

# Specify the IEEE 1588 version 2 PTP profile.

[DeviceB-ptp-instance-2] ptp profile 1588v2

# Specify the P2PTC clock node type.

[DeviceB-ptp-instance-2] ptp mode p2ptc

# Specify PTP domain 2.

[DeviceB-ptp-instance-2] ptp domain 2

# Specify the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceB-ptp-instance-2] ptp source 10.10.1.1

[DeviceB-ptp-instance-2] quit

# Specify PTP for obtaining the time on the default MDC. (Skip this step if this setting has been configured.)

[DeviceB] clock protocol ptp mdc 1

# Assign HundredGigE 3/0/3 to PTP instance and enter interface PTP instance view. Specify IPv4 UDP encapsulation of PTP messages and enable PTP.

[DeviceB] interface hundredgige 3/0/3

[DeviceB-HundredGigE3/0/3] ptp instance 2

[DeviceB-HundredGigE3/0/3-ptp-instance-2] ptp transport-protocol udp

[DeviceB-HundredGigE3/0/3-ptp-instance-2] ptp enable

[DeviceB-HundredGigE3/0/3-ptp-instance-2] quit

[DeviceB-HundredGigE3/0/3] quit

# Assign HundredGigE 3/0/4 to PTP instance and enter interface PTP instance view. Specify IPv4 UDP encapsulation of PTP messages and enable PTP.

[DeviceB] interface hundredgige 3/0/4

[DeviceB-HundredGigE3/0/4] ptp instance 2

[DeviceB-HundredGigE3/0/4-ptp-instance-2] ptp transport-protocol udp

[DeviceB-HundredGigE3/0/4-ptp-instance-2] ptp enable

[DeviceB-HundredGigE3/0/4-ptp-instance-2] quit

[DeviceB-HundredGigE3/0/4] quit

c. Configure Device E:

# Create a PTP instance, specifying its ID as 2 and name as ptp2, and enter its view.

<DeviceE> system-view

[DeviceE] ptp instance 2 name ptp2

# Specify the IEEE 1588 version 2 PTP profile.

[DeviceE-ptp-instance-2] ptp profile 1588v2

# Specify the OC clock node type.

[DeviceE-ptp-instance-2] ptp mode oc

# Specify PTP domain 2.

[DeviceE-ptp-instance-2] ptp domain 2

# Specify the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceE-ptp-instance-2] ptp source 10.10.3.1

[DeviceE-ptp-instance-2] quit

# Specify PTP for obtaining the time on the default MDC.

[DeviceE] clock protocol ptp mdc 1

# Assign HundredGigE 3/0/4 to PTP instance 2 and enter interface PTP instance view. Specify IPv4 UDP encapsulation of PTP messages and the peer delay measurement mechanism and enable PTP.

[DeviceE] interface hundredgige 3/0/1

[DeviceE-HundredGigE3/0/1] ptp instance 2

[DeviceE-HundredGigE3/0/1-ptp-instance-2] ptp transport-protocol udp

[DeviceE-HundredGigE3/0/1-ptp-instance-2] ptp delay-mechanism p2p

[DeviceE-HundredGigE3/0/1-ptp-instance-2] ptp enable

[DeviceE-HundredGigE3/0/1-ptp-instance-2] quit

[DeviceE-HundredGigE3/0/1] quit

Verifying the configuration

1. Verify the configuration of PTP instance 1.

When the network is stable, perform the following tasks to verify the configuration of PTP instance 1.

¡ Use the display ptp clock command to display PTP clock information.

¡ Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information for PTP instance 1 on Device A.

[DeviceA] display ptp clock instance 1

PTP profile : IEEE 1588 Version 2

PTP mode : OC

Slave only : No

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 1

Number of PTP ports : 1

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 0 (ns)

Mean path delay : 0 (ns)

Steps removed : 0

Local clock time : Tue Jul 23 09:41:50 2019

# Display brief PTP running information for all PTP interfaces on Device A.

[DeviceA] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 1 Master E2E Two 0

# Display PTP clock information for PTP instance 1 on Device B.

[DeviceB] display ptp clock instance 1

PTP profile : IEEE 1588 Version 2

PTP mode : E2ETC

Slave only : No

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 1

Number of PTP ports : 2

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : N/A

Mean path delay : N/A

Steps removed : N/A

Local clock time : Tue Jul 23 09:41:50 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 1 N/A E2E Two 0

HGE3/0/2 1 N/A E2E Two 0

HGE3/0/3 2 N/A P2P Two 0

HGE3/0/4 2 N/A P2P Two 0

The command output shows that Device A is elected as the GM, and HundredGigE3/0/1 on Device A sends time synchronization information to its downstreams as a master port.

2. Verify the configuration of PTP instance 2.

When the network is stable, perform the following tasks to verify the configuration of PTP instance 2:

¡ Use the display ptp clock command to display PTP clock information.

¡ Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information for PTP instance 2 on Device D.

[DeviceD] display ptp clock instance 2

PTP profile : IEEE 1588 Version 2

PTP mode : OC

Slave only : No

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 2

Number of PTP ports : 1

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 0 (ns)

Mean path delay : 0 (ns)

Steps removed : 0

Local clock time : Tue Jul 23 09:41:50 2019

# Display brief PTP running information for all PTP interfaces on Device D.

[DeviceD] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 2 Master P2P Two 0

# Display PTP clock information for PTP instance 2 on Device B.

[DeviceB] display ptp clock instance 2

PTP profile : IEEE 1588 Version 2

PTP mode : P2PTC

Slave only : No

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 2

Number of PTP ports : 2

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 106368539000 (ns)

Mean path delay : 2791000 (ns)

Steps removed : 1

Local clock time : Tue Jul 23 09:41:50 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 1 N/A E2E Two 0

HGE3/0/2 1 N/A E2E Two 0

HGE3/0/3 2 N/A P2P Two 0

HGE3/0/4 2 N/A P2P Two 0

The command output shows that Device D is elected as the GM, and HundredGigE3/0/1 on Device D sends time synchronization information to its downstreams as a master port.

Example: Configuring PTP (IEEE 802.1AS, IEEE 802.3/Ethernet encapsulation, multicast transmission)

Network configuration

As shown in Figure 7, a PTP domain contains Device A, Device B, and Device C.

· Configure all devices to use the IEEE 802.1AS PTP profile.

· Specify the OC clock node type for Device A and Device C, and the P2PTC clock node type for Device B. All clock nodes elect a GM through BMC based on their respective default GM attributes.

· Configure the peer delay measurement mechanism (p2p) for Device A and Device C.

· All clock nodes in the PTP domain use the default peer delay measurement mechanism.

Figure 7 Network diagram

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Procedure

IMPORTANT:

The IEEE 802.1AS PTP profile supports IEEE 802.3/Ethernet encapsulation rather than IPv4 UDP encapsulation of PTP messages and multicast transmission rather than unicast transmission of PTP messages.

1. Configure Device A:

# Specify the IEEE 802.1AS PTP profile.

<DeviceA> system-view

[DeviceA] ptp profile 802.1AS

# Specify the OC clock node type.

[DeviceA] ptp mode oc

# Create a PTP domain.

[DeviceA] ptp domain 0

# Specify PTP for obtaining the time on the default MDC.

[DeviceA] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1.

[DeviceA] interface hundredgige 3/0/1

[DeviceA-HundredGigE3/0/1] ptp enable

[DeviceA-HundredGigE3/0/1] quit

2. Configure Device B:

# Specify the IEEE 802.1AS PTP profile.

<DeviceB> system-view

[DeviceB] ptp profile 802.1AS

# Specify the P2PTC clock node type.

[DeviceB] ptp mode p2ptc

# Create a PTP domain.

[DeviceB] ptp domain 0

# Specify PTP for obtaining the time on the default MDC.

[DeviceB] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1.

[DeviceB] interface hundredgige 3/0/1

[DeviceB-HundredGigE3/0/1] ptp enable

[DeviceB-HundredGigE3/0/1] quit

# Enable PTP on HundredGigE 3/0/2.

[DeviceB] interface hundredgige 3/0/2

[DeviceB-HundredGigE3/0/2] ptp enable

[DeviceB-HundredGigE3/0/2] quit

3. Configure Device C:

# Specify the IEEE 1588 802.1AS PTP profile.

<DeviceC> system-view

[DeviceC] ptp profile 802.1AS

# Specify the OC clock node type.

[DeviceC] ptp mode oc

# Create a PTP domain.

[DeviceC] ptp domain 0

# Specify PTP for obtaining the time on the default MDC.

[DeviceC] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1.

[DeviceC] interface hundredgige 3/0/1

[DeviceC-HundredGigE3/0/1] ptp enable

[DeviceC-HundredGigE3/0/1] quit

Verifying the configuration

When the network is stable, perform the following tasks to verify that Device A is elected as the GM, HundredGigE3/0/1 on Device A is the master port, and Device B has synchronized to Device A:

· Use the display ptp clock command to display PTP clock information.

· Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information on Device A.

[DeviceA] display ptp clock

PTP profile : IEEE 802.1AS

PTP mode : OC

Slave only : No

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 0

Number of PTP ports : 1

Priority1 : 246

Priority2 : 248

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 16640

Offset from master : 0 (ns)

Mean path delay : 0 (ns)

Steps removed : 0

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device A.

[DeviceA] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 Master P2P Two 0

# Display PTP clock information on Device B.

[DeviceB] display ptp clock

PTP profile : IEEE 802.1AS

PTP mode : P2PTC

Slave only : No

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 0

Number of PTP ports : 2

Priority1 : 246

Priority2 : 248

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 16640

Offset from master : 106368539000 (ns)

Mean path delay : 2791000 (ns)

Steps removed : 1

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 N/A P2P Two 0

HGE3/0/2 0 N/A P2P Two 0

Example: Configuring PTP (SMPTE ST 2059-2, IPv4 UDP encapsulation, multicast transmission)

Network configuration

As shown in Figure 8, Device A, Device B, and Device C are in a PTP domain. Configure PTP (SMPTE ST 2059-2, multicast transmission) on the three devices as follows for time synchronization:

· Configure the devices to use the SMPTE ST 2059-2 PTP profile.

· Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

· Specify the OC clock node type for Device A and Device C, and the P2PTC clock node type for Device B. All clock nodes elect a GM through BMC based on their respective default GM attributes.

· All clock nodes in the PTP domain use the peer delay measurement mechanism.

Figure 8 Network diagram

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Procedure

IMPORTANT:

The SMPTE ST 2059-2 PTP profile supports IPv4 UDP encapsulation rather than IEEE 802.3/Ethernet encapsulation of PTP messages. It supports both multicast and unicast transmission of PTP messages.

1. Configure Device A:

# Specify the SMPTE ST 2059-2 PTP profile.

<DeviceA> system-view

[DeviceA] ptp profile st2059-2

# Specify the OC clock node type.

[DeviceA] ptp mode oc

# Create a PTP domain.

[DeviceA] ptp domain 0

# Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceA] ptp source 10.10.1.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceA] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify the delay measurement mechanism as p2p and enable PTP.

[DeviceA] interface hundredgige 3/0/1

[DeviceA-HundredGigE3/0/1] ptp transport-protocol udp [DeviceA-HundredGigE3/0/1] ptp delay-mechanism p2p

[DeviceA-HundredGigE3/0/1] ptp enable

[DeviceA-HundredGigE3/0/1] quit

2. Configure Device B:

# Specify the SMPTE ST 2059-2 PTP profile.

<DeviceB> system-view

[DeviceB] ptp profile st2059-2

# Specify the P2PTC clock node type.

[DeviceB] ptp mode p2ptc

# Create a PTP domain.

[DeviceB] ptp domain 0

# Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceB] ptp source 10.10.2.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceB] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, enable PTP.

[DeviceB] interface hundredgige 3/0/1

DeviceB-HundredGigE3/0/1] ptp transport-protocol udp

[DeviceB-HundredGigE3/0/1] ptp enable

[DeviceB-HundredGigE3/0/1] quit

# On HundredGigE 3/0/2, enable PTP.

[DeviceB] interface hundredgige 3/0/2

[DeviceB-HundredGigE3/0/2] ptp transport-protocol udp

[DeviceB-HundredGigE3/0/2] ptp enable

[DeviceB-HundredGigE3/0/2] quit

3. Configure Device C:

# Specify the SMPTE ST 2059-2 PTP profile.

<DeviceC> system-view

[DeviceC] ptp profile st2059-2

# Specify the OC clock node type.

[DeviceC] ptp mode oc

# Create a PTP domain.

[DeviceC] ptp domain 0

# Configure the source IP address for multicast PTP messages transported over IPv4 UDP.

[DeviceC] ptp source 10.10.3.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceC] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify the delay measurement mechanism as p2p and enable PTP.

[DeviceC] interface hundredgige 3/0/1

[DeviceC-HundredGigE3/0/1] ptp delay-mechanism p2p

[DeviceC-HundredGigE3/0/1] ptp enable

[DeviceC-HundredGigE3/0/1] quit

Verifying the configuration

When the network is stable, perform the following tasks to verify the PTP configuration:

· Use the display ptp clock command to display PTP clock information.

· Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information on Device A.

[DeviceA] display ptp clock

PTP profile : SMPTE ST 2059-2

PTP mode : OC

Slave only : No

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 0

Number of PTP ports : 1

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 0 (ns)

Mean path delay : 0 (ns)

Steps removed : 0

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device A.

[DeviceA] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 Master P2P Two 0

# Display PTP clock information on Device B.

[DeviceB] display ptp clock

PTP profile : SMPTE ST 2059-2

PTP mode : P2PTC

Slave only : No

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 0

Number of PTP ports : 2

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 106368539000 (ns)

Mean path delay : 2791000 (ns)

Steps removed : 1

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 N/A P2P Two 0

HGE3/0/2 0 N/A P2P Two 0

The output shows that Device A is elected as the GM and HundredGigE3/0/1 on Device A is the master port.

Example: Configuring PTP (AES67-2015, IPv4 UDP transport, multicast transmission)

Network configuration

As shown in Figure 9, Device A, Device B, and Device C are in a PTP domain. Configure PTP (AES67-2015 profile, IPv4 UDP transport, multicast transmission) on the three devices as follows for time synchronization:

· Specify the AES67-2015 PTP profile and multicast IPv4 UDP transport of PTP messages for Device A, Device B, and Device C.

· Specify the OC clock node type for Device A and Device C, and the P2PTC clock node type for Device B. All clock nodes elect a GM through BMC.

· Use the peer delay measurement mechanism on all clock nodes in the PTP domain.

Figure 9 Network diagram

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Procedure

IMPORTANT:

The AES67-2015 PTP profile supports IPv4 UDP transport rather than IEEE 802.3/Ethernet transport of PTP messages. It supports both multicast and unicast transmission of PTP messages.

‌

1. Configure Device A:

# Specify the AES67-2015 PTP profile.

<DeviceA> system-view

[DeviceA] ptp profile aes67-2015

# Specify the OC clock node type.

[DeviceA] ptp mode oc

# Create a PTP domain.

[DeviceA] ptp domain 0

# Enable PTP globally.

[DeviceB] ptp global enable

# Configure the source IP address for multicast PTP messages transmitted over IPv4 UDP.

[DeviceA] ptp source 10.10.1.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceA] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify the peer delay measurement mechanism and enable PTP.

[DeviceA] interface hundredgige 3/0/1

[DeviceA-HundredGigE3/0/1] ptp delay-mechanism p2p

[DeviceA-HundredGigE3/0/1] ptp enable

[DeviceA-HundredGigE3/0/1] quit

2. Configure Device B:

# Specify the AES67-2015 PTP profile.

<DeviceB> system-view

[DeviceB] ptp profile aes67-2015

# Specify the P2PTC clock node type.

[DeviceB] ptp mode p2ptc

# Create a PTP domain.

[DeviceB] ptp domain 0

# Enable PTP globally.

[DeviceB] ptp global enable

# Configure the source IP address for multicast PTP messages transmitted over IPv4 UDP.

[DeviceB] ptp source 10.10.2.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceB] clock protocol ptp mdc 1

# Enable PTP on HundredGigE 3/0/1,.

[DeviceB] interface hundredgige 3/0/1

[DeviceB-HundredGigE3/0/1] ptp enable

[DeviceB-HundredGigE3/0/1] quit

# Enable PTP on HundredGigE 3/0/2.

[DeviceB] interface hundredgige 3/0/2

[DeviceB-HundredGigE3/0/2] ptp enable

[DeviceB-HundredGigE3/0/2] quit

3. Configure Device C:

# Specify the AES67-2015 PTP profile.

<DeviceC> system-view

[DeviceC] ptp profile aes67-2015

# Specify the OC clock node type.

[DeviceC] ptp mode oc

# Create a PTP domain.

[DeviceC] ptp domain 0

# Enable PTP globally.

[DeviceC] ptp global enable

# Configure the source IP address for multicast PTP messages transmitted over IPv4 UDP.

[DeviceC] ptp source 10.10.3.1

# Specify PTP for obtaining the time on the default MDC.

[DeviceC] clock protocol ptp mdc 1

# On HundredGigE 3/0/1, specify the peer delay measurement mechanism and enable PTP.

[DeviceC] interface hundredgige 3/0/1

[DeviceC-HundredGigE3/0/1] ptp delay-mechanism p2p

[DeviceC-HundredGigE3/0/1] ptp enable

[DeviceC-HundredGigE3/0/1] quit

Verifying the configuration

When the network is stable, perform the following tasks to verify the PTP configuration:

· Use the display ptp clock command to display PTP clock information.

· Use the display ptp interface brief command to display brief PTP running information for all PTP interfaces.

# Display PTP clock information on Device A.

[DeviceA] display ptp clock

PTP global state : Enabled

PTP profile : AES67-2015

PTP mode : OC

Slave only : No

Lock status : Locked

Clock ID : 000FE2-FFFE-FF0000

Clock type : Local

Clock domain : 0

Number of PTP ports : 1

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : 106368539000 (ns)

Mean path delay : 2791000 (ns)

Steps removed : 1

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device A.

[DeviceA] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 Master P2P Two 0

# Display PTP clock information on Device B.

[DeviceB] display ptp clock

PTP global state : Enabled

PTP profile : AES67-2015

PTP mode : P2PTC

Slave only : No

Lock status : Locked

Clock ID : 000FE2-FFFE-FF0001

Clock type : Local

Clock domain : 0

Number of PTP ports : 2

Priority1 : 128

Priority2 : 128

Clock quality :

Class : 248

Accuracy : 254

Offset (log variance) : 65535

Offset from master : N/A

Mean path delay : N/A

Steps removed : N/A

Local clock time : Sun Jan 15 20:57:29 2019

# Display brief PTP running information for all PTP interfaces on Device B.

[DeviceB] display ptp interface brief

Name InstID State Delay mechanism Clock step Asymmetry correction

HGE3/0/1 0 N/A P2P Two 0

HGE3/0/2 0 N/A P2P Two 0

The output shows that Device A is elected as the GM and HundredGigE3/0/1 on Device A sends time synchronization information to its downstreams as a master port.

13-Network Management and Monitoring Configuration Guide

Basic concepts

PTP profile

PTP domain

PTP instance

Optimal PTP domain

Clock node and PTP port

Master-member/subordinate relationship

Clock source type

Grandmaster clock

Specifying PTP for obtaining the time

About this task

Restrictions and guidelines

Procedure

Specifying a PTP profile

Restrictions and guidelines

Procedure

Restrictions and guidelines

Configuring an OC to operate only as a member clock

About this task

Restrictions and guidelines

Procedure

About this task

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Restrictions and guidelines

Procedure

‌About this task

Restrictions and guidelines

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Restrictions and guidelines

Procedure

Configuring PTP message transmission and receipt

Setting the interval for sending announce messages and the timeout multiplier for receiving announce messages

About this task

Procedure

About this task

Restrictions and guidelines

Procedure

Specifying the IPv4 UDP transport protocol for PTP messages

About this task

Restrictions and guidelines

Procedure

Configuring a source IP address for multicast PTP messages transported over IPv4 UDP

About this task

Restrictions and guidelines

Procedure

Configuring a destination IP address for unicast PTP messages transported over IPv4 UDP

About this task

Restrictions and guidelines

Prerequisites

Procedure

About this task

Restrictions and guidelines

Procedure

Setting a DSCP value for PTP messages transmitted over UDP

About this task

Restrictions and guidelines

Procedure

About this task

Procedure

About this task

Procedure

About this task

Procedure

About this task

Restrictions and guidelines

Procedure

About this task

Procedure

Example: Configuring PTP (IEEE 1588 version 2, IEEE 802.3/Ethernet encapsulation, multicast transmission)

Network configuration

Procedure