Jagged little (sync) pill: Enabling installation-based networks for accurate phase delivery and assurance
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The document discusses the concept of a 'sync pill' that enables accurate phase delivery and assurance for network elements requiring synchronization. It highlights the challenges of providing precise phase synchronization, particularly in LTE networks, and suggests that the 'sync pill' can help mitigate issues related to asymmetry and packet delay variation. Furthermore, it details how the 'sync pill' can be used to monitor sync and assure reliability in various network configurations without relying on GNSS.
Jagged little (sync) pill: Enabling installation-based networks for accurate phase delivery and assurance
- 1. Jagged little (sync) pill Enabling installation-based networks for accurate phase delivery and assurance Nir Laufer, director PLM ITSF 2017
- 2. © 2017 ADVA Optical Networking. All rights reserved. Confidential.2 This presentation will not be about Alanis Morissette’s iconic album ...
- 3. © 2017 ADVA Optical Networking. All rights reserved. Confidential.3 Jagged little (sync) pill • Imagine we could have a jagged little sync pill … • A pill that can be swallowed by any network element that requires accurate frequency and phase … • A pill that can be swallowed by any network element that requires sync probing and assurance …
- 4. © 2017 ADVA Optical Networking. All rights reserved. Confidential.4 SyncPill example SyncPlug GM PRTC/PRC BCSlave SyncProbe GNSS input PTP/Sync-E in/out
- 5. © 2017 ADVA Optical Networking. All rights reserved. Confidential.5 Game of the day: Find the SyncPill …
- 6. © 2017 ADVA Optical Networking. All rights reserved. Confidential.6 Grandmaster clock and PRTC enabler • LTE-TDD/ LTE-A base station and small cells require stringent phase synchronization • Delivering accurate phase from the core is challenging due to PDV and asymmetry • Problems can be bypassed by locating our “SyncPill” GM/PRTC closer to the end application, e.g., in first aggregation node T-GM GNSS PTP grandmaster Packet-based backhaul network T-SC T-SC First aggregation node T-SC GNSS High PDV asymmetry
- 7. © 2017 ADVA Optical Networking. All rights reserved. Confidential.7 How can we use core GM for backup? • We can use PTP input from the core GM as backup to the SyncPill GM • Asymmetry between the SyncPill GM and the core GM can be calibrated using GNSS • How can we improve the frequency stability (MTIE/TDEV) of the clock recovered from the PTP backup? T-GM GNSS PTP grandmaster Packet-based backhaul network T-SC T-SC First aggregation node T-SC GNSS High PDV asymmetry GM/APTS
- 8. © 2017 ADVA Optical Networking. All rights reserved. Confidential.8 How can we use core GM for backup? • PDV typically accumulates exponentially as a function of number PTP unaware hops; adding BCs between the GM and slave can reduce PDV significantly (increasing the probability of lucky packets) • We can use our SyncPill as BC enabler to existing network elements – no GNSS is necessary! • The BC will not eliminate the static asymmetry – which can be compensated by the SyncPill GM, but it will improve the frequency stability T-GM GNSS PTP grandmaster Packet-based backhaul network T-SC T-SC First aggregation node T-SC GNSS GM/APTS BC High PDV asymmetry
- 9. © 2017 ADVA Optical Networking. All rights reserved. Confidential.9 Sync-E “pseudo wire” using PTP • How can we bridge Sync-E unaware networks? • SyncPill can function as GM and slave • SyncPill can translate between Sync-E and PTP (freq) and vice versa • No GNSS is necessary! Packet-based backhaul network First aggregation node Translate from PTP to Sync-E Sync-E unaware network SyncPill PTP slave PTP PRC/PRTC GNSS Translate from Sync-E to PTP Sync-E Sync-E Sync-E PTP
- 10. © 2017 ADVA Optical Networking. All rights reserved. Confidential.10 • What is the minimal HW needed in a SyncPill to allow in service sync monitoring and assurance? • Reference (e.g., from GNSS) • Signal under test (SUT) • Time error (TE) / time interval error (TIE) counters • Networking capabilities which allow to send the collected data for analysis in the cloud • Everything else can done in the cloud SyncDoctor Sync probing and assurance
- 11. © 2017 ADVA Optical Networking. All rights reserved. Confidential.11 Syncjack in SyncPlug … • GNSS/PTP/SYNC-E/PPS/CLK as source • GNSS/PTP/SYNC-E/PPS/CLK as reference
- 12. © 2017 ADVA Optical Networking. All rights reserved. Confidential.12 Probing third-party BC/slave • SyncPlug is used for sync assurance of third-party physical clock • Slave/BC 1PPS/10MHz/2.048MHz/Sy nc-E/PTP can be monitored vs. SyncPlug using GNSS as reference • Collected TE/TIE data is sent from SyncPlug to a server for analysis and reporting GNSS SyncPlug BC/slave clock (DUT) 10MHz/2.048MHZ/PPS PTP/Sync-E Sync-E/PTP Master Network TE/TIE raw data SCP/FTP TE/TIE raw data packets Analysis TE/MTIE/TDEV/ reports/alarms … PTP/Sync-E
- 13. © 2017 ADVA Optical Networking. All rights reserved. Confidential.13 Probing a third-party master port • The SyncPlug is used for sync assurance of a third-party BC or GM master port (DUT) • The SyncPlug functions as slave clock / active probe and performs measurements simultaneously (active PTP probe) • Collected timestamps (packet TE/TIE , T2- T1 ,T4-T3) data is sent from SyncPlug to server GNSS SyncPlugBoundary clock (DUT) PTP Master Network TE/TIE raw data SCP/FTP T1 T2 T4 T3 TE/TIE raw data packets PTP packets Analysis TE/MTIE/TDEV/ reports/alarms … PTP
- 14. © 2017 ADVA Optical Networking. All rights reserved. Confidential.14 Active probing of the network • SyncPlug functions as active probe and uses the internal telecom slave packets exchanged via the network (IP unicast – G.8265.1/G.8275.2) • The SyncPlug can probe the network and recover the clock simultaneously • Timestamp (T2-T1 and T4-T3) data is sent from SyncPlug to server SyncPlug (SUT) PTP Master Network TE/TIE raw data SCP/FTP T2 T3 TE/TIE raw data packets PTP packets T1 T4 PTP Analysis TE/MTIE/TDEV/ reports/alarms … GNSS
- 15. © 2017 ADVA Optical Networking. All rights reserved. Confidential.15 Come and pick your SyncPill ... Many sicknesses – one cure Remember to take your Sync Pill!
- 16. IMPORTANT NOTICE The content of this presentation is strictly confidential. ADVA Optical Networking is the exclusive owner or licensee of the content, material, and information in this presentation. Any reproduction, publication or reprint, in whole or in part, is strictly prohibited. The information in this presentation may not be accurate, complete or up to date, and is provided without warranties or representations of any kind, either express or implied. ADVA Optical Networking shall not be responsible for and disclaims any liability for any loss or damages, including without limitation, direct, indirect, incidental, consequential and special damages, alleged to have been caused by or in connection with using and/or relying on the information contained in this presentation. Copyright © for the entire content of this presentation: ADVA Optical Networking. Thank You IMPORTANT NOTICE The content of this presentation is strictly confidential. ADVA Optical Networking is the exclusive owner or licensee of the content, material, and information in this presentation. Any reproduction, publication or reprint, in whole or in part, is strictly prohibited. The information in this presentation may not be accurate, complete or up to date, and is provided without warranties or representations of any kind, either express or implied. ADVA Optical Networking shall not be responsible for and disclaims any liability for any loss or damages, including without limitation, direct, indirect, incidental, consequential and special damages, alleged to have been caused by or in connection with using and/or relying on the information contained in this presentation. Copyright © for the entire content of this presentation: ADVA Optical Networking. nlaufer@advaoptical.com