CalConnect XLIII - September 24-27, 2018

CalConnect XLIII in Karlsruhe, Germany, hosted by 1&1
Monday, September 24, 2018 to Thursday, September 27, 2018
Subscribe to the CalConnect Week Calendar.
Recent Changes: 

2018-09-26 Adjusted Thursday schedule to accommodate work sessions in afternoon.

2018-09-24 Thursday schedule re-arranged, feedback sessions added.

2018-09-23 Wednesday schedule slightly re-arranged, added "Authoring CalConnect Standards" Lab to Wednesday afternoon. Monday and Tuesday schedules changed slightly.

2018-09-20 Minor schedule/session changes, addition of session on JMAP for Calendar and Contacts.

2018-09-11 Minor schedule/session changes and additions, event calendar updated.

2018-09-07 Conference registration fee adjusted.

2018-09-03 CalConnect rate at conference hotel available through 19 September or when the room block is exhausted.

2018-08-14 Minor schedule/session changes, event calendar updated.

2018-07-26 Subscribable (webdav) calendar for the event added.

2018-07-24 Minor schedule/session changes; additional information for train bookings in transportation.

2018--07-18 Preliminary Conference schedule and sessions added

2018-07-06 Added information and link about Public Workshop Monday afternoon the 24th.

CalConnect XLIII will be held in Karlsruhe, Germany, on September 24-27, 2018, hosted by 1&1. 

This event is the first preview of  our new conference format.  CalConnect XLIII will be four days (Monday through Thursday), and brings together, as a single event and with a single fee, our traditional conference (Conference Track), with  elements of the former developers' forum (Technical Track). The two tracks are simply a handy guide to the session  content, and all attendees are encouraged to attend sessions in both tracks. We will use your feedback and experience at Karlsruhe to help us fine-tune our new conference for events in 2019 and beyond.

CalConnect XLIII is open to members, and to non-members as observers.

General Format:  Monday morning will be the opening of the technical track and an introduction for first-time attendees and observers.  Monday afternoon will be the opening of the conference track, including status of CalConnect activities, and other CalConnect business, and a Public Workshop to introduce Calendaring & Scheduling to developers, which will be advertised in the Karlsruhe IT community.   Tuesday, Wednesday and Thursday mornings will be conference track, afternoons will be technical track.  The general content of the tracks is below; the Schedule section will include sessions for both the conference and technical tracks.

Conference track:

  • Strategic topics and discussions.
  • Decisions on CalConnect business
  • Small BOF sessions to gauge interest
  • Small sessions to report on progress in technical tracks

Technical track:

  • In depth discussions - possibly smaller groups as follow up from topics started at the conference
  • in depth BOF sessions
  • Face-to-face versions of TC calls
  • Development of data formats, protocols, standards (incl. Whiteboard work).
  • Joint work on CalConnect efforts such as the CalDAV Tester, iCal4J, DEVGUIDE, perhaps a reference specification for CalDAV or JSCalendar or...
  • Test Lab: testing of new components, testing and resolution of bugs and issues, test requests from TCs to confirm application behavior.

Public Workshop:  Monday 24 September, 1600-1730 - Introduction into Calendaring, Scheduling, address book and Date&Time, followed by a reception at 1800.  See for more information.

International Visitors 

In general most CalConnect participants will not require a Visa to visit Germany. However if you are unsure, please see German VISA Information.

Conference Details 

We will begin each day at 0830 (rather than 0800 as in the past) with coffee.  The first session will be at 0900 (rather than 0830). The default end for each day is now 1730 rather than 1800. 

Morning coffee (or tea) will be accompanied by fruit; however, you should plan to have your real breakfast prior to arriving at the venue.

Registration Information 

Registration is now open for CalConnect XLIII; please see to register.  There is only one registration and one payment per person for the entire event.


CalConnect XLIII will be held at the 1&1 facilities in Karlsruhe, at Ernst-Frey-Straße 10, 76135 Karlsruhe, Germany. The venue is less than a kilometer walk from the conference hotel, Hotel Santo, Karlstraße 67-69, 76137 Karlsruhe, Germany.  Please note that the home page for the hotel is not available in English; English information may be found at

Here is a map showing the locations of the venue, the hotel, and the main train station:

For more information about Karlsruhe please see


If you will be arriving and departing by air, plan on arriving at Frankfurt International Airport (FRA) and take the train from Frankfurt Flughafen Fernbahnhof to Karlsruhe. The train station is physically within the Frankfurt airport. The train operates on an hourly basis (direct or via Mannheim), and will cost about 80€ to Karlsruhe and back (flexible rate, less if you fix the time in advance),  Please see for booking information in English. 

The central train station at Karlsruhe is close to the conference hotel and the venue:

Within Karlsruhe, either walk or use the tram: day ticket 6,40 € (10,60 € for a group up to 5); single ride 2 €.

Please Note:  Credit cards are not necessarily accepted universally in Germany, in particular by taxis.  ATMs (cash tills) should be available at all airports, train stations, etc. and you should provide yourself with some cash if you haven't already.



The conference hotel is the Hotel Santo, Karlstraße 67-69, 76137 Karlsruhe, Germany.  Please note that the home page for the hotel is not available in English; English information may be found at

1&1 have reserved a block of 15 rooms for us at a rate of 80€ incl. WLAN and breakfast (without our rate it is 130-150€) per night, between September 23 and September 28. The rate will be available until a few days before the event (essentially 19 September) or if all 15 rooms are booked earlier.

To obtain the rate you need to write an email to Julia Becker ( including the dates (from-to), your Name and your email address. Julia will inform the hotel of requests, and the hotel will send a confirmation email directly to the attendee.  Please allow up to a week to receive the confirmation.

The rate will be paid by each attendee as our service is just to provide the lower rate.

Conference Schedule 


Monday Morning 24 September - TECHNICAL TRACK
0830-0900 Coffee, Fruit
 0900-0930 Technical Track Opening
Sign up for Test Lab, additional discussion topics, etc.
0930-1030 In-depth discussion: Server-Side Subscriptions
1030-1100 Break and Refreshments
1100-1200 Introduction to CalConnect Q&A
An optional session for first-time attendees. The genesis of CalConnect, a brief history, how CalConnect works, followed by questions.
1100-1215 CalConnect CalDAV Tester status and joint work
Making tests more generally applicable
1215-1230 Technical Track wrapup and status for day
1230-1330 Lunch
Monday Afternoon 24 September - CONFERENCE TRACK
 1330-1400 Conference Track Opening
Welcome, logistics, introductions
1400-1430 Reports on CalConnect Activities
TC activity, IETF liaison, Report from the Board
1430-1500 New and Non-Member Presentations
Short introductions to new/non members attending
1500-1530 Review of Technical Track discussions of special note
1530-1600 Break and refreshments
1600-1730 Public Workshop: Introduction to Calendaring & Scheduling
1730-1930 Welcome Reception
On premises
Tuesday Morning 25 September - CONFERENCE TRACK
0830-0900 Coffee, Fruit
 0900-0945 Developers Guide
Presenting current status, new hosting option, request for content
0945-1030 "Party Crashing" proposed specification
What to do about uninvited attendees
1030-1100 Break and Refreshments
1100-1200 Review current work and status
Series in Calendar Data, Server-Side Subscriptions, Streaming Calendar Data, Subscription upgrade. TZDIST, TZ Geolocation specs
1200-1230 BOF: EU Time Zone direction and CalConnect actions (position paper, workshop at next event?)
1230-1330 Lunch
Tuesday Afternoon 25 September - TECHNICAL TRACK
 1330-1430 In-depth discussion: Streaming Calendar Data
1430-1530 RRULE expansion in existing implementations
Review and generate test cases following the discussion on the tc calendar mailing list and planned CalConnect position paper
1530-1600 Break and refreshments
1600-1715 In-depth discussion: Abuse audit draft
How to store information on how an event ends up on someone’s calendar including exchange of audit information between server and client
1715-1730 Technical Track wrapup and status for day
Wednesday Morning 26 September - CONFERENCE TRACK
0830-0900 Coffee, Fruit
0900-1000 CalConnect Standards, Publishing and Co-Publishing
As result of our liaisons with other bodies, we will start publishing work done together with these bodies again, to show our contribution and raise the awareness of CalConnect being a standards body. Exchange about what’s needed to do so (projects, new processes, voting).
1000-1030 CalConnect Liaisons with other standards bodies
With which bodies, why, what are we doing, value provided, how to get involved
1030-1100 Break and Refreshments
1100-1130 Introduction to CalConnect/ISO 8601-2
 1130-1230 Calendar Spam
Presenting status of Best Practices Document and process with M3AAWG as well as feedback from technical track session on abuse audit draft
1230-1330 Lunch
Wednesday Afternoon 26 September - TECHNICAL TRACK
 1330-1430 Authoring CalConnect Standards Lab
Using Asciidoc and GitHub Repositories to author and publish CalConnect Standards
 1430-1530 TC VCARD, ISO TC 211, ISO 19160
Universal address profiles and evolution of vCard
1530-1600 Break and refreshments
1600-1630 JSCalendar status, technical issues
Review specification moving forward to last call for draft, extensions for address data and tasks
1630-1715 JMAP for Calendar and Contacts
Review JMAP Core status and work on a data model for synchronizing calendar and contacts data with a server using JMAP.
1715-1730 Technical Track wrapup and status for day
1915-2130 Conference Dinner
Thursday Morning 27 September - COMBINED
0830-0900 Coffee, Fruit
0900-0930 Feedback on Standards Activities and New Confence Format
0930-1000 ISO TC 37 update
Potential for TC on Languages/I18N/L10N
1000-1030 Handling ETags in CalDAV
The use of ETags in CalDAV appears to conflict with the specifications. We will try to develop a recommended approach.
1030-1100 Break and Refreshments
1100-1130 CalDAV handling of public or shared calendars
Supporting searching for, subscriptions and invitations to public calendars
1130-1145 Technical Committee Directions for period to CalConnect XLIV
1145-1230 CalConnect Plenary Meeting
Administrative business, coming events, consensus agreements on decisions reached during the week, open floor.
1230-1330 Lunch
Thursday Afternoon 27 September - Working Sessions
 1330-1500 DevGuide Joint Work
Work on increasing the content of DEVGUIDE following the short list of demanded/suggested content
 1330-1700 CalDAV Tester Joint Work
1530-1600 Break and refreshments
1700 Close of CalConnect XLIII



Please see the Reading List for the Conference at