1 / 13

Improvement for gPTP Gen 1 (IEEE 802.1 AS)

Improvement for gPTP Gen 1 (IEEE 802.1 AS). 08-01- 2013 IEEE 802.1 Plenary Meeting – Orlando Marcel Kießling, Siemens AG Franz-Josef Götz, Siemens AG. Structure of this Presentation. Recap of basic mechanisms Announce Frame Sync Frame Recap of the previous presented possible solutions

lavey
Download Presentation

Improvement for gPTP Gen 1 (IEEE 802.1 AS)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Improvement for gPTP Gen 1 (IEEE 802.1 AS) 08-01- 2013 IEEE 802.1 Plenary Meeting – Orlando Marcel Kießling, Siemens AG Franz-Josef Götz, Siemens AG

  2. Structure of this Presentation • Recap of basic mechanisms • Announce Frame • Sync Frame • Recap of the previous presented possible solutions • Network with “old” stored information • Proposed Solutions • Preferred Solution • Usage of the “syncReceiptTimeout” • Identification of the GM in the Sync

  3. Type of FramesSync- and Announce Frames • All gPTP frames are P2P frames • Announce frames • Elect best Grandmaster • Port Role (Slave / Master) • Sync frames • Time Sync • Path Delay frames • Measure Path/Link Delay • Request • Response • Response Follow Up

  4. Announce frame • Every device starts with periodically sending Announce Messages every announce interval • Announce Messages include the time-synchronization spanning tree vectors • Best Master Clock Algorithm (BMCA) uses these vectors to set up the loop-free Sync Tree (like BPDUs for the RSTP Tree) • Established Sync Tree

  5. Sync frame • Sync Frame is send more frequently than Announce Frames and includes information for synchronization • Follow the given sync tree established through announce frames • Loop prevention by using loop-free sync tree

  6. Problem with the 802.1 as Sync Tree • Stations with a Passive Port should not answer with old, previously stored information • Ring-Topology with stored GM Information's

  7. Structure of this Presentation • Recap of basic mechanisms • Announce Frame • Sync Frame • Recap of the previous presented possible solutions • Network with “old” stored information • Proposed Solutions • Preferred Solution • Usage of the “syncReceiptTimeout” • Identification of the GM in the Sync

  8. previous presented possible solutions • Optimized path trace TLV • Avoid long Announce Messages • Hop-Count • How to get a useful maximum Number • Deletion of stored information • What should cause the deletion • Using a special frame information • Like proprietary solutions • Using an timeout • Sync Messages are send out more often

  9. Structure of this Presentation • Recap of basic mechanisms • Announce Frame • Sync Frame • Recap of the previous presented possible solutions • Network with “old” stored information • Proposed Solutions • Preferred Solution • Usage of the “syncReceiptTimeout” • Identification of the GM in the Sync

  10. Usage of the “syncReceiptTimeout” • Definition: • Use the “syncReceiptTimeout” to • delete the stored information of the old GM on all ports (Passive Ports) • rerun the BMCA (without old information)

  11. Open Problem in Gen 1? – Identification of the GM • GM identification is not needed up to now because: • Only one GM exists • no Identification • Sync follow the loop free path • Port Roles block wrong frames

  12. Open Problem for Gen 2! – Identification of the GM • High Available Synchronization

  13. Thank you for your attention! Improvement for gPTP Gen 1 (IEEE 802.1 AS) Marcel Kießling Innovation Manager I IA SC IC TI Phone: +49(911)-895 3888 E-Mail: kiessling.marcel@siemens.com

More Related