Subject: [TICTOC] Minutes TICTOC IETF 75

From: <[email-masked]>
Date: Tue, 18 Aug 2009 10:32:31 +0200

Dear all,

Please find attached the minutes of TICTOC WG meeting during IETF 75 in Stockholm.
Questions and comments are welcome.

Best Regards,

Sébastien JOBERT
R&D engineer, network synchronization
Orange Labs / France Telecom R&D
FT/RD/CORE/MCN/WAN
Tel : +33 2 96 05 20 93 - Mob : +33 6 82 69 00 50 
[email-masked]

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IETF TICTOC Working Group Meeting
Monday, July 27, 2009, 1740-1940

The jabber log can be found at:
http://jabber.ietf.org/logs/tictoc/2009-07-27.txt

The meeting was called to order by co-chairs Yaakov Stein and Stewart Bryant. Sébastien Jobert took the minutes. There was no volunteer to act as jabber  scribe; however, Stewart monitored the jabber room and provided comments from remote attendees. The blue sheets were distributed, and the  agenda was presented with no additions (http://www.ietf.org/proceedings/75/agenda/tictoc.txt). 

Status Update, Yaakov Stein
===========================
Slides: tictoc-0 (http://www.ietf.org/proceedings/75/slides/tictoc-0.ppt)

Yaakov presented the status of the current working group work items and documents.

The requirements draft is now officially a WG draft (WG00 draft, http://www.ietf.org/id/draft-ietf-tictoc-requirements-00.txt).
It was pointed out that Silvana Rodrigues, editor of this draft but not present during this IETF75 meeting, plans to remotely continue editing this draft. Karen was therefore asked by Yaakov to present the updates of this draft, on behalf of Silvana, later during the meeting.

The architecture draft (http://tools.ietf.org/html/draft-stein-tictoc-modules) was briefly discussed; no progress was made since the last IETF meeting.

The work regarding other drafts has not started.

It was explained that several conference calls have been organised in order to progress on the requirements draft. During those calls, there was a feeling that definitions would be needed. Instead of keeping those definitions within the requirements draft, it was considered preferable to create a new dedicated document. However, this new document was not ready (still in early stages) and therefore not presented during IETF 75 (only slides intending to summarize the discussions have been presented).

Attendees were reminded that conference calls would continue being organised to progress the work. These calls take place on the first and third Thursday of each month, and reminders are sent to the list.

NTP status update, Karen O'Donoghue
===================================
Slides:  tictoc-5 (http://www.ietf.org/proceedings/75/slides/tictoc-5.ppt)

Karen presented the status of NTP on going items:
- NTPv4 protocol: IESG evaluation
- NTPv4 MIB: IESG evaluation
- NTP Autokey: IESG evaluation (AD follow-up)
- NTP server DHCPv6: second WG last call (few endorsements)

Following this presentation, there has been a short discussion regarding the DHCP draft. The conclusion was that the NTP DHCPv6 draft needs DHCP WGs review.

Requirements draft update, Karen O'Donoghue (slides prepared by Silvana Rodrigues)
==================================================================================
Document:  http://www.ietf.org/id/draft-ietf-tictoc-requirements-00.txt
Slides:  tictoc-4 (http://www.ietf.org/proceedings/75/slides/tictoc-4.ppt)

Karen presented the short summary of the requirements document status, prepared by Silvana.
The format of the tables has been changed. It was pointed out that requirements are still missing for industrial and networking applications.
Comments on the draft are welcome.

Definitions draft, Yaakov Stein
===============================
Slides:  tictoc-3 (http://www.ietf.org/proceedings/75/slides/tictoc-3.ppt)

Yaakov presented a short summary of the discussions on definitions which happened during the TICTOC conference calls.
The presentation contains the terms "frequency", "phase", "aligned phase", "labeled time", and "calibrated time", as well as "stability", "accuracy", "holdover", and the "on-path support" concept.

It was reminded that the intention is to reference the existing definitions in other SDOs (such as ITU-T Q13/15), when possible.
It was also said that the presented definitions were not yet agreed, and that the work is still on-going.
There was a request to submit a document providing the discussed definitions so that the participants could review them.

Then, a long discussion started regarding some terms contained in the slides, for clarification, especially regarding the concept of "on-path support".

1588v2 time synchronization modules, Fei Su
===========================================
Slides:  tictoc-2 (http://www.ietf.org/proceedings/75/slides/tictoc-2.ppt)

Fei provided a set of slides discussing how PTPv2 could be used to deliver time synchronization to base stations (e.g. for TD-SCDMA systems), together with frequency synchronization (delivered at the physical layer) support (such as combination with Synchronous Ethernet). The slides contain a description of different possible modules. Fei explained that this document has been merged with another I-D previously presented.

There was a remark after the presentation regarding the degree of overlap of the proposed work with activities already on-going in other SDOs (such as, for instance, ITU-T Q13/15, which was clearly referenced in the presentation). Some participants also attending to ITU-T Q13/15 confirmed that some work is currently on-going in ITU-T regarding the definition of a PTP profile time-oriented, including the possible combination with Synchronous Ethernet. The TICTOC chairs clarified that TICTOC does not wish to duplicate work that is already on-going elsewhere, but that TICTOC could cover any other aspects which are not handled and where TICTOC or IETF has expertise. The security aspects of the PTP profiles were felt as a possible study item for TICTOC.

Femto Cell synchronization, Rock Xie
====================================
Slides:  tictoc-1 (http://www.ietf.org/proceedings/75/slides/tictoc-1.ppt)

Rock presented an analysis of the femto cells application and its related implications on synchronization delivery.
3 main challenges regarding synchronization were depicted in the presentation: security, connectivity, and scalability.
The presentation pointed out the potential issues on synchronization flows (e.g. higher PDV) when using mechanisms such as IP Sec or NAT.

Discussion took place as to whether this femtocell application would need to be added in the requirements draft, or if it is already sufficiently covered.
There was a comment that the Femto Cell Forum, working on femto cell aspects, has not investigated the synchronization aspects of femto cells in details.
It was however clarified that the Femto Cell Forum had not asked the IETF to work on this problem, and that this presentation was not an official request from the Femto Cell Forum.

There were short comments on security aspects: it was said that other security mechanisms than the one discussed in the presentation could also have been considered for the synchronization flow.

It was asked what was the specific synchronization protocol targeted in this presentation. Rock replied that this presentation did not intend to discuss a protocol in particular, but rather the general requirements associated to femto cells. It was said that a similar presentation has also been done in ITU-T Q13/15, with a clear discussion towards PTP protocol. But it was also mentioned that many femto cell implementations rely today on NTP protocol.

The meeting was adjourned around 1915.