No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search

Reminder

To have a better experience, please upgrade your IE browser.

upgrade

S12700 V200R010C00 Configuration Guide - Device Management

This document describes the principles and configurations of the Device Management features, and provides configuration examples of these features.

Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Licensing Requirements and Limitations for PTP

Licensing Requirements and Limitations for PTP

Involved Network Elements

BITS clock source

Licensing Requirements

PTP is not under license control.

Version Requirements

Table 5-2  Applicable product models and versions

Product

Product Model

Software Version

S12700

S12704, S12708, S12710, and S12712

V200R010C00

Feature Limitations

PTP Constraints

  • All the intermediate devices on the PTP synchronization path must support PTP.
  • The switch must be configured with a CKM-clock daughter card and the cards that support the 1588v2 function. If the switch is equipped with double main control units, a CKM-clock daughter card must be installed in each main control unit. The following cards support the 1588v2 function: X series (except the ET1D2G48TX1E card).The 1588v2 function takes effect only after the enhanced working mode is configured using the set service-mode command on the cards.

  • An interface does not support the PTP function after switching to the WAN mode.
  • An MPU has two BITS interfaces: BITS0 and BITS1. BITS0 receives frequency signals, and BITS1 receives time signals.
  • When the PTP system needs to receive external clock signals through BITS interfaces, the same BITS interfaces (BITS0 for example) on the clock cards of active and standby MPUs, must receive the same external clock signals. If the device has only one MPU installed, only the BITS interface of the MPU needs to receive external clock signals.
  • Frequency signals are transmitted bidirectionally, and time signals are transmitted unidirectionally. The cable that transmits time signals is a straight-through cable, and the cable that transmits frequency signals is a crossover cable.
  • PTP Announce messages contain the clock attributes of the peer device to establish the master-slave hierarchy of interfaces. Therefore, a PTP interface is allowed to receive only one type of Announce messages.

PTP Precautions

  • Ensure that frequency synchronization is implemented on the entire network through synchronous Ethernet. For details about synchronous Ethernet, see "Configuring Synchronous Ethernet" in Device Management Configuration Guide.
  • PTP messages are Layer 2 broadcast messages by default. If incorrect configuration is performed, loops or broadcast storms occur and downstream devices are seriously affected. To avoid loops or broadcast storms, configure VLAN or STP before enabling PTP on an interface.
  • By default, a device obtains frequency signals through synchronous Ethernet and obtains time signals through PTP. When PTP is used for clock synchronization, you are advised to configure the device to obtain frequency signals and time signals through PTP.
  • On a switch with two MPUs, frequent active/standby switchovers (within 15 minutes) may result in a jitter of 400 ns. You are advised to perform other operations 20 minutes later than an active/standby switchover.

PTP Device Types

The device supports the following clock types:

  • OC: Ordinary clock
  • BC: Boundary clock
  • End to end transparent clock (E2ETC) for the delay mechanism

    It is a TC using delay measurement mechanism in delay mode. When the device functions as an E2ETC, the device does not need to have the delay measurement mechanism mode configured.

  • Peer to peer transparent clock (P2PTC) for the Pdelay mechanism

    It is a TC using delay measurement mechanism in Pdelay mode. When the device functions as a P2PTC, the device does not need to have the delay measurement mechanism mode configured.

  • TCandBC

    It provides some PTP ports that function as a BC to synchronize time with or to other clocks, and provides some PTP ports that function as a TC to transmit PTP messages without calculating the link delay.

  • End to end transparent clock and ordinary clock (E2ETCOC)

    It provides some ports that function as a TC and synchronizes the frequency with upstream devices based on PTP messages. The ports that function as a TC use the delay measurement mechanism in delay mode.

  • Peer to peer transparent clock and ordinary clock (P2PTCOC)

    It provides some ports that function as a TC and synchronizes the frequency with upstream devices based on PTP messages. The ports that function as a TC use the delay measurement mechanism in Pdelay mode.

Translation
Download
Updated: 2019-12-28

Document ID: EDOC1000142080

Views: 123999

Downloads: 155

Average rating:
This Document Applies to these Products

Related Version

Related Documents

Share
Previous Next