ws-calendar — archive

[Gershon Janssen]

Draft minutes of the TC meeting are available at http://www.oasis-open.org/apps/org/workgroup/ws-calendar/download.php/37432/Minutes_WS-Calendar-TC_20100416_Draft.txt Regards, Gershon Janssen --- DRAFT MINUTES Web Services Calendar (WS-Calendar) TC 16 April 2010 12:00pm ET, 06:00pm CET Call-In Information: Australia: +61 (0) 7 3123 6030 Austria: +43 (0) 7 20881407 Belgium: +32 (0) 28 08 4297 Canada: +1-778-785-0724 Denmark: +45 69 91 88 70 Finland: +358 942 599 697 France: +33 (0) 182 880 463 Germany: +49 (0) 898 7806 6464 Ireland: +353 (0) 14 845 983 Italy: +39 0553989569 Netherlands: +31 (0) 208 080 385 New Zealand: +64 (0) 4 974 7216 Norway: +47 21 04 29 13 Spain: +34 955329911 Sweden: +46 (0) 313 613 559 Switzerland: +41 (0) 225 3314 55 United Kingdom: +44 (0) 203 318 4725 United States: +1-626-521-0010 Access Code: 114-622-898 No need for an audio PIN Thanks to LONMARK for the conference call support. NEW ACTION ITEMS: - Kavi #0014 / AI20100416-001 - Toby Considine Send links to relevant Internet time standards to TC Scribe: Gershon Janssen 0. Roll call, Agenda review Meeting Attendees Name Company Status ----- ------- ------ Toby Considine University of North Carolina Chair Gershon Janssen Individual Secretary William Cox Cox Software Architects LLC Member Jeremy Roberts LonMark International* Member Carl Mattocks CheckMi Member Gale Horst Electric Power Research Inst Member David Thewlis CalConnect Member Ed Koch Akuacom Inc. Member Benoit Lepeuple LonMark International* Member Eric Chan Oracle Corporation Observer Bernard Desruisseaux Oracle Corporation Observer Paul Tischhauser Microsoft Observer Ed Cazalet Indiviual Observer This meeting quorates. No changes and / or additions to the agenda. 1. Minutes Approval Meeting minutes of 02 April 2010 (http://www.oasis-open.org/apps/org/workgroup/ws-calendar/download.php/37374/Minutes_WS-Calendar-TC_20100402_Draft.txt) are approved pending the addition of Dave Thewlis to the list of attendants. Meeting minutes of 09 April 2010 (http://www.oasis-open.org/apps/org/workgroup/ws-calendar/download.php/37369/Minutes_WS-Calendar-TC_20100409_Draft.txt) are approved unanimously. 2. FYI / announcements from Chair, Secretary, Liaison * Chair: Gershon Janssen: T: As a TC we cannot use materials that have been send or provided by non-members (e.g. observers). Gershon Janssen: T: example: ICOM PDF can be used within the ICOM TC, but not within this TC, as we need approval for this. Gershon Janssen: EC (observer): amend the email with an invitation to ICOM and to participate in the ICOM TC. Gershon Janssen: Second issue: internet time standards have a minimal granularity of one second, which are not granular enough for our standard Gershon Janssen: T: will provide links to standards; this needs to be addressed by this TC Gershon Janssen: T: the format does not allow for anything else than seconds. Jeremy J. Roberts: YYYY-MM-DDThh:mm:ss * Secretary: None * Liaison: Gershon Janssen: DT: Since RFC 5545 (iCALENDAR) does not deal with fractional seconds there is no way of introducing them into the specification without a very signficant change as it would affect a number of different parts of the spec. It would certainly introduce a compatibility issue. However it is possible to introduce the concept into xCal by defining it in the xCal XML namespace, and an XML object containing that could be carried along in an iCalendar data stream and available upon reconversion into xCal - it just wouldn't make sense in iCalendar. This is probably not an issue with respect to the smart grid work, and at this point we do not see the need to introduce fractional seconds in iCalendar itself so long as the issue can be addressed in xCal. We are going to include a proposal to handle the fractional seconds issue in our web services calendar specification which should be available to WS CALENDAR very soon. 3. Open Action Item Review and Discussion For action items overview, please refer to: http://www.oasis-open.org/apps/org/workgroup/ws-calendar/members/action_items.php - Kavi #0000 / AI20100305-001 - Toby Considine Request Jira access for the TC Issues list Issues Tracking System now Live http://www.oasis-open.org/apps/org/workgroup/ws-calendar/email/archives/201004/msg00019.html Action item ready and can be closed. - Kavi #0011 / AI20100402-001 - Benoit Lepeuple Provide references to OPC 3.0 specs on time Scheduled for discussion during this call. - Kavi #0012 / AI20100402-002 - Benoit Lepeuple Draw up a short outline on timestamping, data timestamping in OPC, etc. Scheduled for discussion during this call. 4. Discuss issues Discussion on documents / submittals. * Discuss draft FAQ http://www.oasis-open.org/committees/download.php/37249/FAQ_WS-Calendar_20100409_wd-01.doc Bill has to leave early; postponed to next call. * [Benoit Lepeuple] Note on clock and timestamp handling in OPC http://www.oasis-open.org/apps/org/workgroup/ws-calendar/email/archives/201004/msg00022.html Gershon Janssen: BL: wrote a note on timestamping with respect to OPC and IEC61850 Gershon Janssen: BL: elaborates on note: http://www.oasis-open.org/apps/org/workgroup/ws-calendar/email/archives/201004/msg00022.html Gershon Janssen: Time sync protocols track how much they are adjusted and refuse to sync when the time is of to much; this information could be usefull to Benoit's note. Gershon Janssen: Note covers an overview of what has been done in related standards, but does not address a cross-check with the use cases. Gershon Janssen: T: 61850 seems to have the most elaborate model Gershon Janssen: BL: clock not in sync flag is optional in the 61850 spec (quality of time information) Gershon Janssen: T: should the committe work from 61850? Gershon Janssen: DT: See how iCalendar (based on xCAL) as a base will not break when working towards 61850 Gershon Janssen: JR: concerns on backward compatibility Jeremy J. Roberts: "ISO 8601 does not specify the exact meaning of its representations. This means for example that the standard does not define whether 09:00 refers to the exact end of the ninth hour of the day, any other point in the following minute or the minute as a whole. Users of the standard must agree on a more exact interpretation of the representation if this is relevant." -ISO's web site regarding ISO 8601:2004. Gershon Janssen: JR: Question related to both DT and BL -- see post above. XML schema for date/time follows ISO8601 -- does it allow to put in a more accurate time? Gershon Janssen: JR: how to ensure compatibility with e.g. iCal and still capture information, even if we do not intend to use it? Gershon Janssen: T: Any other input on timestamps and granularity? Gershon Janssen: T: Questions to Dave - share this information with Dave's group Dave Thewlis: Benoit's report has been relayed to our TC XML group. Thank you. Jeremy J. Roberts: IETF RFC5545 (Calsify) has the following section... 3.3.6. Duration Value Name: DURATION Purpose: This value type is used to identify properties that contain a duration of time. Format Definition: This value type is defined by the following notation: dur-value = (["+"] / "-") "P" (dur-date / dur-time / dur-week) dur-date = dur-day [dur-time] dur-time = "T" (dur-hour / dur-minute / dur-second) dur-week = 1*DIGIT "W" dur-hour = 1*DIGIT "H" [dur-minute] dur-minute = 1*DIGIT "M" [dur-second] dur-second = 1*DIGIT "S" dur-day = 1*DIGIT "D" Description: If the property permits, multiple "duration" values are specified by a COMMA-separated list of values. The format is based on the [ISO.8601.2004] complete representation basic format with designators for the duration of time. The format can represent nominal durations (weeks and days) and accurate durations (hours, minutes, and seconds). Note that unlike [ISO.8601.2004], this value type doesn't support the "Y" and "M" designators to specify durations in terms of years and months. The duration of a week or a day depends on its position in the calendar. In the case of discontinuities in the time scale, such as the change from standard time to daylight time and back, the computation of the exact duration requires the subtraction or addition of the change of duration of the discontinuity. Leap seconds MUST NOT be considered when computing an exact duration. When computing an exact duration, the greatest order time components MUST be added first, that is, the number of days MUST be added first, followed by the number of hours, number of minutes, and number of seconds. Negative durations are typically used to schedule an alarm to trigger before an associated time (see Section 3.8.6.3). No additional content value encoding (i.e., BACKSLASH character encoding, see Section 3.3.11) are defined for this value type. Example: A duration of 15 days, 5 hours, and 20 seconds would be: P15DT5H0M20S A duration of 7 weeks would be: P7W Gershon Janssen: Discussion on contribution from JR -- see above. Key point is concept of duration. Jeremy J. Roberts: YYYY-Www-D where YYYY is the Year in the Gregorian calendar (2010), ww is the week of the year between 01 (the first week) and 52 or 53 (the last week), and D is the day in the week between 1 (Monday) and 7 (Sunday). Naturally, those in the US are thinking? "Week of the year? Who uses that?" We don't because it's different in the US than in Europe, for example. Our week starts on Sunday (not Monday) and our year's first week is not the same as ISO's first week definition. Gershon Janssen: Concept of a week (week of the year) is not common in the US, though in Europe its common. Gershon Janssen: Toby has to leave the call, Gershon is chair for the remainder of the meeting. Jeremy J. Roberts: It should be noted that the ISO 8601:2004 standard costs between $103.20 and $129.00 (depending on membership discount) and a hardcopy cost of $162.00. Gershon Janssen: Are we going to follow Jeremy's advice on the concept of week? So should WS-Calendar support this or not? Gershon Janssen: DT: In RFC 5545 (iCALENDAR) the concept of "week" exists only in the context of DURATION and there is no way to point to a specific week. * Girish Ghatikar / Interval Definition for Price Responsive DR: http://www.oasis-open.org/committees/download.php/37215/Interval-definition.pdf No more time on call, item deferred to next call. 5. Any Other Business? None. 6. Adjourn Gershon Janssen: Meeting adjourned