- play_arrow Overview
- play_arrow Precision Time Protocol
- play_arrow Precision Time Protocol Overview
- play_arrow Precision Time Protocol Clocks
- PTP Boundary Clock Overview
- Example: Configure PTP Boundary Clock
- Example: Configure PTP Boundary Clock With Unicast Negotiation
- Configure PTP TimeTransmitter Clock
- Configure PTP TimeReceiver Clock
- Example: Configure Ordinary TimeReceiver Clock With Unicast-Negotiation
- Example: Configure Ordinary TimeReceiver Clock Without Unicast-Negotiation
- PTP Transparent Clocks
- Configure PTP Transparent Clock
- play_arrow Precision Time Protocol Profiles
- play_arrow PHY Timestamping
- play_arrow Precision Time Protocol over Ethernet
- PTP over Ethernet Overview
- Guidelines to Configure PTP over Ethernet
- Configure PTP Dynamic Ports for Ethernet Encapsulation
- Configure PTP Multicast TimeTransmitter and TimeReceiver Ports for Ethernet Encapsulation
- Example: Configure PTP over Ethernet for Multicast TimeTransmitter, TimeReceiver, and Dynamic Ports
- play_arrow Precision Time Protocol Additional Features
- Precision Time Protocol (PTP) over Link Aggregation Group (LAG)
- Precision Time Protocol (PTP) Trace Overview
- Line Card Redundancy for PTP
- Timing Defects and Event Management on Routing Platforms
- SNMP MIB for Timing on Routing Platforms
- PTP Passive Port Performance Monitoring on PTX10004 and PTX10008 Devices
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- play_arrow Network Time Protocol
- play_arrow NTP Concepts
- play_arrow NTP Configuration Examples
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- play_arrow Synchronous Ethernet
- play_arrow Synchronous Ethernet Overview
- play_arrow Synchronous Ethernet on 10-Gigabit Ethernet MIC
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- play_arrow Clock Synchronization
- play_arrow Clock Synchronization Concepts
- play_arrow Clock Synchronization for ACX Series Routers
- play_arrow Clock Synchronization for MX Series Routers
- play_arrow Clock Synchronization for PTX Series Routers
- play_arrow Centralized Clocking
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- play_arrow Hybrid Mode
- play_arrow Hybrid Mode Overview
- play_arrow Hybrid Mode and ESMC Quality-Level Mapping
- Configure Hybrid Mode and ESMC Quality-Level Mapping Overview
- Configure Hybrid Mode with Mapping of the PTP Clock Class to the ESMC Quality-Level
- Configure Hybrid Mode with a User-Defined Mapping of the PTP Clock Class to the ESMC Quality-Level
- Example: Configure Hybrid Mode and ESMC Quality-Level Mapping on ACX Series Router
- Example: Configure Hybrid Mode and ESMC Quality-Level Mapping on MX240 Router
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- play_arrow Configuration Statements and Operational Commands
- play_arrow Appendix
Integrated Global Navigation Satellite System (GNSS) on Routing Platforms
GNSS is a navigation aid system that uses signals from satellites to calculate the actual position of a GPS-capable receiver. These signals are not only used for determining the position of the receiver on Earth but also as a very accurate time base. Juniper provides routers that have the GNSS receiver integrated within the system. These routers support Telecom Grandmaster (T-GM) functionality.
Global Navigation Satellite System (GNSS) is a navigation aid system that uses signals from satellites to calculate the actual position of a GPS-capable receiver. These signals are not only used for determining the position of the receiver on Earth but also as a very accurate time base.
Juniper provides routers with the GNSS receiver integrated within the platform. This eliminates the need to have an external GPS receiver. Routers integrated with the GNSS receivers support the Telecom Grandmaster (T-GM) functionality. The T-GM acts as a G8275.1 T-GM (ordinary clock) by synchronizing itself to an internal/external GNSS receiver and drives time and frequency to the downstream PTP slaves via timestamps in PTP packets.
The inbuilt GPS receiver can be hooked to a GPS antenna to be able to receive GPS time. It then uses PTP to distribute this time to other network devices. The router enables GNSS input through SubMiniature version A (SMA) connector.
The ACX500, ACX7332, and ACX7348 routers support integrated GNSS receivers. Review the platform's hardware guide for more details.
Configuration
edit chassis synchronization] hierarchy level. You must also configure
the PTP settings under the [edit protocols ptp] hierarchy. Configuring T-GM for ACX7332 and ACX7348 Routers
Configure the GNSS settings under the [
set chassis synchronization] hierarchy. You must specify at least oneconstellationoption. A sample configuration snippet for mandatory GNSS configuration is provided below:content_copy zoom_out_mapset chassis synchronization gnss-receiver 0 receiver-type internal set chassis synchronization gnss-receiver 0 interface set chassis synchronization gnss-receiver 0 constellation gps l1ca
Optionally, you can also configure the following GNSS options:
content_copy zoom_out_mapset chassis synchronization gnss-receiver 0 position mode survey-mode survey-length 5 set chassis synchronization gnss-receiver 0 position-mode position-fix-mode latitude 90 longitude 180 altitude 0 set chassis synchronization gnss-receiver 0 cable-delay-compensation 100000 set chassis synchronization gnss-receiver 0 snr-threshold 10 set chassis synchronization gnss-receiver 0 disable-log set chassis synchronization network-option option-1 set chassis synchronization esmc-transmit interfaces ge-0/0/0 set chassis synchronization enable-extended-ql-tlv
Configure PTP T-GM configuration under the [
set protocols ptp]hierarchy. A sample configuration snippet is provided below:content_copy zoom_out_mapset protocols ptp clock-mode ordinary set protocols ptp profile-type g.8275.1 set protocols ptp master interface et-0/0/0.0 multicast-mode transport ieee-802.3
Verify GNSS configuration:
content_copy zoom_out_mapuser@host> show chassis synchronization gnss-receiver time Current ToD : 00:00:00 00/00/0 UTC Pending : FALSE UTC offset (TAI-UTC) : 0 Future leap sec & schedule : 00 00:00:00 00/00/0
content_copy zoom_out_mapuser@host> show chassis synchronization gnss-receiver version Product Name : GF8801 OPUS7_SFLASH_MP_64P Product Rev/version : ENP708C2109100T Additional Information : None
content_copy zoom_out_mapuser@host> show chassis synchronization gnss-receiver Lock status : Fine lock Receiver-type : Internal Serial Number : 751700984 Port Status : Up Port Details : UART 9600 bps / USB Current ToD : 23:46:30 05/01/2024 UTC Pending : FALSE UTC offset (TAI-UTC) : 37 Future leap sec & schedule : 38 00:00:00 01/01/2024 1PPS STATUS : Available 10mhz status : Available Time source : UTC (USNO) Alarms : NONE Antenna port status : Open Constellation : GPS L1CA Position mode : Position-fix-mode Self Survey Length : 0 mins Cable Delay Compensation : 0 ns SNR-threshold : 0 dBHz Latitude : 0 0' 0.006000'' N Longitude : 0 0' 0.000000'' W Altitude : -18 m No. of Satellites Used : 12
content_copy zoom_out_mapuser@host> show chassis synchronization gnss-receiver extensive Lock status : Fine lock Receiver-type : Internal Serial Number : 751700984 Port Status : Up Port Details : UART 9600 bps / USB Current ToD : 23:48:06 05/01/2024 UTC Pending : FALSE UTC offset (TAI-UTC) : 37 Future leap sec & schedule : 38 00:00:00 01/01/2024 1PPS STATUS : Available 10mhz status : Available Time source : UTC (USNO) Alarms : NONE Antenna port status : Open Constellation : GPS L1CA Position mode : Position-fix-mode Self Survey Length : 0 mins Cable Delay Compensation : 0 ns SNR-threshold : 0 dBHz Latitude : 0 0' 0.006000'' N Longitude : 0 0' 0.000000'' W Altitude : -18 m No. of Satellites Used : 12 Visible Satellite List: Sat-Num Signal-level Status Type 20 43 dBHz Acquired GPS 1 43 dBHz Acquired GPS 7 42 dBHz Acquired GPS 23 42 dBHz Acquired GPS 25 42 dBHz Acquired GPS 19 42 dBHz Acquired GPS 8 42 dBHz Acquired GPS 13 42 dBHz Acquired GPS 11 42 dBHz Acquired GPS 28 42 dBHz Acquired GPS 3 42 dBHz Acquired GPS 4 41 dBHz Acquired GPS
content_copy zoom_out_mapuser@host> show chassis synchronization extensive Current clock status : LOCKED Clock locked to : Primary SNMP trap status : Disabled Configured ports: Name : gnss-rx-0 Current ToD : Fri Jan 05 15:48:54 2024 PST Last ToD update : Fri Jan 05 15:48:53 2024 PST GPS receiver status : Synchronized UTC Pending : FALSE UTC Offset : 37 One PPS status : Active {master}Verify PTP T-GM configuration:
content_copy zoom_out_mapuser@host> show ptp lock-status detail Lock Status: Lock State : 5 (PHASE ALIGNED) State since : 2024-07-25 23:53:29 PDT (4d 10:07 ago) Source: GNSS
Configuring T-GM for ACX500 Routers
- Configure the GNSS settings under the [
set chassis synchronization] hierarchy. If you do not specify aconstellationoption, then the gps constellation option is considered by default. A sample configuration snippet is provided below:content_copy zoom_out_mapset chassis synchronization network-option option-1 set chassis synchronization selection-mode received-quality set chassis synchronization clock-mode auto-select set chassis synchronization quality-mode-enable set chassis synchronization port gnss client cable-length-compensation 20 set chassis synchronization port gnss client constellation gps-qzss set chassis synchronization port gnss client anti-jamming set chassis synchronization esmc-transmit interfaces ge-0/0/0 set chassis synchronization esmc-transmit interfaces ge-0/0/1 set chassis synchronization esmc-transmit interfaces ge-0/1/0
Configure PTP T-GM configuration under the [
set protocols ptp]hierarchy. A sample configuration snippet is provided below:content_copy zoom_out_mapset protocols ptp clock-mode ordinary set protocols ptp profile-type g.8275.1 set protocols ptp transparent-clock set protocols ptp priority1 128 set protocols ptp priority2 128 set protocols ptp domain 12 set protocols ptp unicast-negotiation set protocols ptp master pseudo-holdover-time 1920 set protocols ptp master pseudo-holdover-cooldown-time 300 set protocols ptp master holdover-in-specification-time 3600 set protocols ptp master interface ge-0/0/0.0 unicast-mode transport ipv4 set protocols ptp master interface ge-0/0/0.0 unicast-mode clock-client 192.168.0.2/32 local-ip-address 192.168.0.10 set protocols ptp master interface ge-0/0/1.0 unicast-mode transport ipv4 set protocols ptp master interface ge-0/0/1.0 unicast-mode clock-client 10.0.0.2/32 local-ip-address 10.0.0.10
Verify the GNSS configuration:
content_copy zoom_out_mapuser@host> show chassis synchronization extensive Aug 22 16:27:05 Configured ports: Name : gnss Current ToD : Wed Aug 22 16:27:05 2018 Last ToD update : Wed Aug 22 16:27:04 2018 GPS receiver status : Synchronized UTC Pending : FALSE UTC Offset : 37 One PPS status : Active
content_copy zoom_out_mapuser@host> show chassis synchronization gnss extensive Aug 22 16:25:15 Receiver Status : Good Constellation : GPS + QZSS Cable delay compensation : 20 Antenna Status : GPS Antenna Good Position : 35 39' 1.708827'' N : 139 45' 21.107670'' E Altitude : 78 meters Number of satellites : 9 Satellite List: Sat No Signal Level Status Type Mode(T=Timing/P=Position) 13 41 dBHZ Acquired GPS T,P 2 43 dBHZ Acquired GPS T,P 195 41 dBHZ Acquired QZSS T,P 6 46 dBHZ Acquired GPS T,P 5 46 dBHZ Acquired GPS T,P 9 22 dBHZ Acquired GPS T,P 19 39 dBHZ Acquired GPS T,P 193 42 dBHZ Acquired QZSS T,P
Verify the PTP T-GM configuration:
content_copy zoom_out_mapuser@host> show ptp lock-status detail Aug 28 10:05:52 Lock Status: Lock State : 5 (PHASE ALIGNED) State since : 2017-09-19 12:45:47 JST (48w6d 21:20 ago) Source: External GPS/GNSS
content_copy zoom_out_mapuser@host> show ptp global-information Aug 28 10:07:22 PTP Global Configuration: Domain number : 12 Clock mode : Ordinary PTP Profile Type : ITU-G.8275.1 Priority Level1 : 128 Priority Level2 : 128 Unicast Negotiation : Enabled ESMC QL From Clock Class : Disabled Clock Class/ESMC QL : - SNMP Trap Status : Enabled Transparent-clock-config : ENABLED Transparent-clock-status : ACTIVE Slave Parameters: Sync Interval : -4 (16 packets per second - unicast request) Delay Request Interval: -6 (64 packets per second - unicast request) Announce Interval : -3 (8 packets per second - unicast request) Announce Timeout : 3 Grant Duration : 300
content_copy zoom_out_mapuser@host> show ptp clock detail Aug 28 15:44:46 Clock Details: Slot Number : 0 Default Data: Two-step Clock : FALSE Clock Identity : 30:7c:5e:ff:fe:3f:65:00 Total Ports on Device : 32 Clock Class : 248 Clock Accuracy : 254 Log Variance : 20061 Clock Priority1 : 128 Clock Priority2: 128 UTC Offset : 37 Leap59 : FALSE Leap61 : FALSE Time Tracable : FALSE Frequency Tracable : FALSE Time Source : 0 Delay Req Sending Time: 0 Steps Removed : 0 Slave-only : NA Parent Data: Parent Id : 30:7c:5e:ff:fe:3f:65:00 GMC Id : 30:7c:5e:ff:fe:3f:65:00 GMC Class : 6 GMC Accuracy : 33 GMC Variance : 20061 GMC Priority1 : 128 GMC Priority2 : 128 Global Data: UTC Offset : 37 Leap-59 : FALSE Leap-61 : FALSE Time tracable : TRUE Freq Traceable : TRUE Time Scale : TRUE
Note:The range for
cable-length-compensationis from 0 to 50000000 nanoseconds.The integrated GNSS receiver in the ACX500 series routers do not support 10-MHz frequency input and output.
PTP is not supported on 1G ports across all platforms. Refer PTP Features and Supported Platforms for information on PTP platforms and supported PTP features.
