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Daboo 3 Internet-Draft Apple Inc. 4 Intended status: Standards Track October 8, 2015 5 Expires: April 10, 2016 7 New Properties for iCalendar 8 draft-ietf-calext-extensions-01 10 Abstract 12 This document defines a set of new properties for iCalendar data as 13 well as extending the use of some existing properties to the entire 14 iCalendar object. 16 Status of This Memo 18 This Internet-Draft is submitted in full conformance with the 19 provisions of BCP 78 and BCP 79. 21 Internet-Drafts are working documents of the Internet Engineering 22 Task Force (IETF). Note that other groups may also distribute 23 working documents as Internet-Drafts. The list of current Internet- 24 Drafts is at http://datatracker.ietf.org/drafts/current/. 26 Internet-Drafts are draft documents valid for a maximum of six months 27 and may be updated, replaced, or obsoleted by other documents at any 28 time. It is inappropriate to use Internet-Drafts as reference 29 material or to cite them other than as "work in progress." 31 This Internet-Draft will expire on April 10, 2016. 33 Copyright Notice 35 Copyright (c) 2015 IETF Trust and the persons identified as the 36 document authors. All rights reserved. 38 This document is subject to BCP 78 and the IETF Trust's Legal 39 Provisions Relating to IETF Documents 40 (http://trustee.ietf.org/license-info) in effect on the date of 41 publication of this document. Please review these documents 42 carefully, as they describe your rights and restrictions with respect 43 to this document. Code Components extracted from this document must 44 include Simplified BSD License text as described in Section 4.e of 45 the Trust Legal Provisions and are provided without warranty as 46 described in the Simplified BSD License. 48 Table of Contents 50 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 51 2. Conventions Used in This Document . . . . . . . . . . . . . . 3 52 3. Backwards Compatible Extension Properties . . . . . . . . . . 3 53 4. Modifications to Calendar Components . . . . . . . . . . . . 3 54 5. Properties . . . . . . . . . . . . . . . . . . . . . . . . . 5 55 5.1. NAME Property . . . . . . . . . . . . . . . . . . . . . . 5 56 5.2. DESCRIPTION Property . . . . . . . . . . . . . . . . . . 6 57 5.3. UID Property . . . . . . . . . . . . . . . . . . . . . . 6 58 5.4. LAST-MODIFIED Property . . . . . . . . . . . . . . . . . 7 59 5.5. URL Property . . . . . . . . . . . . . . . . . . . . . . 7 60 5.6. CATEGORIES Property . . . . . . . . . . . . . . . . . . . 7 61 5.7. REFRESH-INTERVAL Property . . . . . . . . . . . . . . . . 7 62 5.8. SOURCE Property . . . . . . . . . . . . . . . . . . . . . 8 63 5.9. COLOR Property . . . . . . . . . . . . . . . . . . . . . 9 64 5.10. IMAGE Property . . . . . . . . . . . . . . . . . . . . . 10 65 5.11. CONFERENCE Property . . . . . . . . . . . . . . . . . . . 11 66 6. Property Parameters . . . . . . . . . . . . . . . . . . . . . 13 67 6.1. DISPLAY Property Parameter . . . . . . . . . . . . . . . 13 68 6.2. EMAIL Property Parameter . . . . . . . . . . . . . . . . 14 69 6.3. FEATURE Property Parameter . . . . . . . . . . . . . . . 15 70 6.4. LABEL Property Parameter . . . . . . . . . . . . . . . . 16 71 7. Security Considerations . . . . . . . . . . . . . . . . . . . 16 72 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 73 8.1. Property Registrations . . . . . . . . . . . . . . . . . 17 74 8.2. Parameter Registrations . . . . . . . . . . . . . . . . . 17 75 8.3. Display Types Registry . . . . . . . . . . . . . . . . . 18 76 8.4. Feature Types Registry . . . . . . . . . . . . . . . . . 18 77 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 18 78 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 18 79 10.1. Normative References . . . . . . . . . . . . . . . . . . 18 80 10.2. Informative References . . . . . . . . . . . . . . . . . 19 81 Appendix A. Change History (To be removed by RFC Editor before 82 publication) . . . . . . . . . . . . . . . . . . . . 19 83 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 21 85 1. Introduction 87 The iCalendar [RFC5545] data format is used to represent calendar 88 data and is used with iTIP [RFC5546] to handle scheduling operations 89 between calendar users. iCalendar is in widespread use, and in 90 accordance with provisions in that specification, extension elements 91 have been added by various vendors to the data format in order to 92 support and enhance capabilities. This specification collects a 93 number of these ad-hoc extensions and uses the new IANA registry 94 capability defined in [RFC5545] to register standard variants with 95 clearly defined definitions and semantics. In addition, some new 96 elements are introduced for features that vendors have recently been 97 requesting. 99 2. Conventions Used in This Document 101 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 102 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 103 "OPTIONAL" in this document are to be interpreted as described in 104 [RFC2119]. 106 The notation used in this memo is the ABNF notation of [RFC5234] as 107 used by iCalendar [RFC5545]. Any syntax elements shown below that 108 are not explicitly defined in this specification come from iCalendar 109 [RFC5545]. 111 3. Backwards Compatible Extension Properties 113 iCalendar defines properties which can have different value types 114 indicated by a "VALUE" parameter. The definition of a property 115 specifies a "default" value type that is assumed to be used when no 116 "VALUE" parameter is present. However, this poses a problem to 117 iCalendar parser/generator software that does not know about the 118 default values for new properties. For example, if a new property 119 "FOO" were defined with a default value type of URI, and a URI value 120 with a comma was used, an iCalendar generator not aware of this fact 121 would likely treat the property value as "TEXT" and apply backslash 122 escaping to the comma in the value, effectively making it an invalid 123 URI value. 125 To avoid this problem, this specification recommends that all 126 properties not defined in [RFC5545], always include a "VALUE" 127 parameter, if the type is other than "TEXT". i.e., in the example 128 above, the "FOO" property would have a "VALUE=URI" parameter. This 129 allows iCalendar parser/generator software to track the correct types 130 of unknown properties. 132 New properties defined in this specification use the term "no 133 default" in the "Value Type" definition to indicate that the "VALUE" 134 parameter has to be included. 136 4. Modifications to Calendar Components 138 The following changes to the syntax defined in iCalendar [RFC5545] 139 are made here. New elements are defined in subsequent sections. 141 calprops /= *( 142 ; 143 ; The following are OPTIONAL, 144 ; but MUST NOT occur more than once. 145 ; 146 uid / last-mod / url / 147 refresh / source / color 148 ; 149 ; The following are OPTIONAL, 150 ; and MAY occur more than once. 151 ; 152 name / description / categories / 153 image 154 ; 155 ) 157 eventprop /= *( 158 ; 159 ; The following are OPTIONAL, 160 ; but MUST NOT occur more than once. 161 ; 162 color / 163 ; 164 ; The following are OPTIONAL, 165 ; and MAY occur more than once. 166 ; 167 image 168 ; 169 ) 171 todoprop /= *( 172 ; 173 ; The following are OPTIONAL, 174 ; but MUST NOT occur more than once. 175 ; 176 color / 177 ; 178 ; The following are OPTIONAL, 179 ; and MAY occur more than once. 180 ; 181 image 182 ; 183 ) 185 jourprop /= *( 186 ; 187 ; The following are OPTIONAL, 188 ; but MUST NOT occur more than once. 189 ; 190 color / 191 ; 192 ; The following are OPTIONAL, 193 ; and MAY occur more than once. 194 ; 195 image 196 ; 197 ) 199 5. Properties 201 5.1. NAME Property 203 Property Name: NAME 205 Purpose: This property specifies the name of the calendar. 207 Value Type: TEXT 209 Property Parameters: IANA, non-standard, alternate text 210 representation, and language property parameters can be specified 211 on this property. 213 Conformance: This property can be specified multiple times in an 214 iCalendar object. However, each property MUST represent the name 215 of the calendar in a different language. 217 Description: This property is used to specify a name of the 218 iCalendar object that can be used by calendar user agents when 219 presenting the calendar data to a user. Whilst a calendar only 220 has a single name, multiple language variants can be specified by 221 including this property multiple times with different "LANGUAGE" 222 parameter values on each. 224 Format Definition: This property is defined by the following 225 notation: 227 name = "NAME" nameparam ":" text CRLF 229 nameparam = *( 230 ; 231 ; The following are OPTIONAL, 232 ; but MUST NOT occur more than once. 233 ; 234 (";" altrepparam) / (";" languageparam) / 235 ; 236 ; The following is OPTIONAL, 237 ; and MAY occur more than once. 238 ; 239 (";" other-param) 240 ; 241 ) 243 Example: The following is an example of this property: 245 NAME:Company Vacation Days 247 5.2. DESCRIPTION Property 249 This specification modifies the definition of the "DESCRIPTION" 250 property to allow it to be defined on an iCalendar object. The 251 following additions are made to the definition of this property. 253 Purpose: This property specifies the description of the calendar. 255 Conformance: This property can be specified multiple times in an 256 iCalendar object. However, each property MUST represent the 257 description of the calendar in a different language. 259 Description: This property is used to specify a lengthy textual 260 description of the iCalendar object that can be used by calendar 261 user agents when describing the nature of the calendar data to a 262 user. Whilst a calendar only has a single description, multiple 263 language variants can be specified by including this property 264 multiple times with different "LANGUAGE" parameter values on each. 266 5.3. UID Property 268 This specification modifies the definition of the "UID" property to 269 allow it to be defined on an iCalendar object. The following 270 additions are made to the definition of this property. 272 Purpose: This property specifies the persistent, globally unique 273 identifier for the iCalendar object. This can be used, for 274 example, to identify duplicate calendar streams that a client may 275 have been given access to. It can be used in conjunction with the 276 "LAST-MODIFIED" property also specified on the "VCALENDAR" object, 277 to identify the most recent version of a calendar. 279 Conformance: This property can be specified once in an iCalendar 280 object. 282 5.4. LAST-MODIFIED Property 284 This specification modifies the definition of the "LAST-MODIFIED" 285 property to allow it to be defined on an iCalendar object. The 286 following additions are made to the definition of this property. 288 Purpose: This property specifies the date and time that the 289 information associated with the calendar was last revised. 291 Conformance: This property can be specified once in an iCalendar 292 object. 294 5.5. URL Property 296 This specification modifies the definition of the "URL" property to 297 allow it to be defined on an iCalendar object. The following 298 additions are made to the definition of this property. 300 Purpose: This property may be used to convey a location where a more 301 dynamic rendition of the calendar information can be found. 303 Conformance: This property can be specified once in an iCalendar 304 object. 306 5.6. CATEGORIES Property 308 This specification modifies the definition of the "CATEGORIES" 309 property to allow it to be defined on an iCalendar object. The 310 following additions are made to the definition of this property. 312 Purpose: This property defines the categories for an entire 313 calendar. 315 Conformance: This property can be specified multiple times in an 316 iCalendar object. 318 5.7. REFRESH-INTERVAL Property 320 Property Name: REFRESH-INTERVAL 321 Purpose: This property specifies a suggested minimum interval for 322 polling for changes of the calendar data from the original source 323 of that data. 325 Value Type: DURATION - no default 327 Property Parameters: IANA and non-standard property parameters can 328 be specified on this property. 330 Conformance: This property can be specified once in an iCalendar 331 object. 333 Description: This property specifies a positive duration that gives 334 a suggested minimum polling interval for checking for updates to 335 the calendar data. The value of this property SHOULD be used by 336 calendar user agents to limit the polling interval for calendar 337 data updates to the minimum interval specified. 339 Format Definition: This property is defined by the following 340 notation: 342 refresh = "REFRESH-INTERVAL" refreshparam 343 ":" dur-value CRLF 344 ;consisting of a positive duration of time. 346 refreshparam = *( 347 ; 348 ; The following is REQUIRED, 349 ; but MUST NOT occur more than once. 350 ; 351 (";" "VALUE" "=" "DURATION") / 352 ; 353 ; The following is OPTIONAL, 354 ; and MAY occur more than once. 355 ; 356 (";" other-param) 357 ; 358 ) 360 Example: The following is an example of this property: 362 REFRESH-INTERVAL;VALUE=DURATION:P1W 364 5.8. SOURCE Property 366 Property Name: SOURCE 367 Purpose: This property identified a URI where calendar data can be 368 refreshed from. 370 Value Type: URI - no default 372 Property Parameters: IANA and non-standard property parameters can 373 be specified on this property. 375 Conformance: This property can be specified once in an iCalendar 376 object. 378 Description: This property identifies a location where a client can 379 retrieve updated data for the calendar. Clients SHOULD honor any 380 specified "REFRESH-INTERVAL" value when periodically retrieving 381 data. Note that this property differs from the "URL" property in 382 that "URL" is meant to provide an alternative representation of 383 the calendar data, rather than the original location of the data. 385 Format Definition: This property is defined by the following 386 notation: 388 source = "SOURCE" sourceparam ":" uri CRLF 390 sourceparam = *(";" other-param) 392 Example: The following is an example of this property: 394 SOURCE;VALUE=URI:http://example.com/holidays.ics 396 5.9. COLOR Property 398 Property Name: COLOR 400 Purpose: This property specifies a color used for displaying the 401 calendar, event, todo, or journal data. 403 Value Type: TEXT 405 Property Parameters: IANA and non-standard property parameters can 406 be specified on this property. 408 Conformance: This property can be specified once in an iCalendar 409 object, or "VEVENT", "VTODO", or "VJOURNAL" calendar components. 411 Description: This property specifies a color that clients MAY use 412 when presenting the relevant data to a user. Typically this would 413 appear as the "background" color of events or tasks. The value is 414 a case-insensitive color name taken from the CSS3 set of names, 415 defined in Section 4.3 of [W3C.REC-css3-color-20110607]. 417 Format Definition: This property is defined by the following 418 notation: 420 color = "COLOR" colorparam ":" text CRLF 421 ; Value is CSS3 color name 423 colorparam = *(";" other-param) 425 Example: The following is an example of this property: 427 COLOR:turquoise 429 5.10. IMAGE Property 431 Property Name: IMAGE 433 Purpose: This property specifies an image associated with the 434 calendar or a calendar component. 436 Value Type: URI or BINARY - no default. The value MUST refer to or 437 be data with a media type of "image". 439 Property Parameters: IANA, non-standard, display, inline encoding, 440 and value data type property parameters can be specified on this 441 property. The format type parameter can be specified on this 442 property and is RECOMMENDED for inline binary encoded content 443 information. 445 Conformance: This property can be specified multiple times in an 446 iCalendar object, or "VEVENT", "VTODO", or "VJOURNAL" calendar 447 components. 449 Description: This property specifies an image for an iCalendar 450 object or a calendar component via a uri or directly with inline 451 data that can be used by calendar user agents when presenting the 452 calendar data to a user. Multiple properties MAY be used to 453 specify alternative sets of images with, for example, varying 454 media subtypes, resolutions or sizes. When multiple properties 455 are present, calendar user agents SHOULD display only one of them, 456 picking one that provides the most appropriate image quality, or 457 display none. The "DISPLAY" parameter is used to indicate the 458 intended display mode for the image. The "ALTREP" parameter, 459 defined in [RFC5545], can be used to provide a "clickable" image 460 where the URI in the parameter value can be "launched" by a click 461 on the image in the calendar user agent. 463 Format Definition: This property is defined by the following 464 notation: 466 image = "IMAGE" imageparam ( ":" uri ) / 467 ( 468 ";" "ENCODING" "=" "BASE64" 469 ";" "VALUE" "=" "BINARY" 470 ":" binary 471 ) / 472 CRLF 474 imageparam = *( 475 ; 476 ; The following is REQUIRED, 477 ; but MUST NOT occur more than once. 478 ; 479 (";" "VALUE" "=" "URI") / 480 ; 481 ; The following is OPTIONAL for a URI value, 482 ; RECOMMENDED for a BINARY value, 483 ; and MUST NOT occur more than once. 484 ; 485 (";" fmttypeparam) / 486 ; 487 ; The following are OPTIONAL, 488 ; and MUST NOT occur more than once. 489 ; 490 (";" altrepparam) / (";" displayparam) / 491 ; 492 ; The following is OPTIONAL, 493 ; and MAY occur more than once. 494 ; 495 (";" other-param) 496 ; 497 ) 499 Example: The following is an example of this property: 501 IMAGE;VALUE=URI;DISPLAY=BADGE;FMTTYPE=image/png:h 502 ttp://example.com/images/party.png 504 5.11. CONFERENCE Property 506 Property Name: CONFERENCE 508 Purpose: This property specifies information for accessing a 509 conferencing system. 511 Value Type: URI - no default. 513 Property Parameters: IANA, non-standard, feature, and label property 514 parameters can be specified on this property. 516 Conformance: This property can be specified multiple times in a 517 "VEVENT" or "VTODO" calendar component. 519 Description: This property specifies information for accessing a 520 conferencing system for attendees of a meeting or task. This 521 might be a tel: URI [RFC3966] for a telephone-based conference 522 number dial-in (with access codes included), or it might be an 523 http: URI [RFC7230] for a web-based video chat, or a URI for an 524 instant messaging group chat room. If a specific URI for a 525 conferencing system is not available, a data: URI [RFC2397] 526 containing a text description can be used. 528 A conference system can be a bi-directional communication channel, 529 or a uni-directional "broadcast feed". 531 The "FEATURE" property parameter is used to describe the key 532 capabilities of the conference system to allow a client to choose 533 the ones that give the required level of interaction from a set of 534 multiple properties. 536 The "LABEL" property paramater is used to convey additional 537 details on the use of the URI. For example, the URIs or access 538 codes for the moderator and attendee of a teleconference system 539 could be different, and the "LABEL" property parameter could be 540 used to "tag" each "CONFERENCE" property to indicate which is 541 which. 543 Format Definition: This property is defined by the following 544 notation: 546 conference = "CONFERENCE" confparam ":" uri CRLF 548 confparam = *( 549 ; 550 ; The following is REQUIRED, 551 ; but MUST NOT occur more than once. 552 ; 553 (";" "VALUE" "=" "URI") / 554 ; 555 ; The following are OPTIONAL, 556 ; and MUST NOT occur more than once. 557 ; 558 (";" featureparam) / (";" labelparam) / 559 ; 560 ; The following is OPTIONAL, 561 ; and MAY occur more than once. 562 ; 563 (";" other-param) 564 ; 565 ) 567 Example: The following are examples of this property: 569 CONFERENCE;VALUE=URI;FEATURE=PHONE,MODERATOR; 570 LABEL=Moderator dial-in:tel:+1-412-555-0123,,,654321 571 CONFERENCE;VALUE=URI;FEATURE=PHONE; 572 LABEL=Attendee dial-in:tel:+1-412-555-0123,,,555123 573 CONFERENCE;VALUE=URI;FEATURE=PHONE; 574 LABEL=Attendee dial-in:tel:+1-888-555-0456,,,555123 575 CONFERENCE;VALUE=URI;FEATURE=CHAT; 576 LABEL=Chat room:xmpp:chat-123@conference.example.com 577 CONFERENCE;VALUE=URI;FEATURE=AUDIO,VIDEO; 578 LABEL=Attendee dial-in:http://chat.example.com/audio?id=123456 580 6. Property Parameters 582 6.1. DISPLAY Property Parameter 584 Parameter Name: DISPLAY 586 Purpose: To specify different ways in which an image for a calendar 587 or component can be displayed. 589 Format Definition: This property parameter is defined by the 590 following notation: 592 displayparam = "DISPLAY" "=" displayval *("," displayval) 594 displayval = ("BADGE" / ; image inline with the title of the 595 ; event 596 "GRAPHIC" / ; a full image replacement for the event 597 ; itself 598 "FULLSIZE / ; an image that is used to enhance the 599 ; event 600 "THUMBNAIL / ; a smaller variant of "FULLSIZE" to be 601 ; used when space for the image is 602 ; constrained 603 x-name / ; Experimental type 604 iana-token) ; Other IANA registered type 605 ; 606 ; Default is BADGE 608 Description: This property parameter MAY be specified on "IMAGE" 609 properties. In the absence of this parameter, the value "BADGE" 610 MUST be used for the default behavior. The value determines how a 611 client ought to present an image supplied in iCalendar data to the 612 user. 614 Values for this parameter are registered with IANA as per 615 Section 8.3. New values can be added to this registry following 616 the procedure outlined in Section 8.2.1 of [RFC5545]. 618 Servers and clients MUST handle x-name and iana-token values they 619 don't recognize by not displaying any image at all. 621 Example: 623 IMAGE;VALUE=URI;DISPLAY=BADGE,THUMBNAIL,;FMTTYPE=image/png:http://exa 624 mple.com/images/weather-cloudy.png 626 6.2. EMAIL Property Parameter 628 Parameter Name: EMAIL 630 Purpose: To specify an email address that is used to identify or 631 contact an organizer or attendee. 633 Format Definition: This property parameter is defined by the 634 following notation: 636 emailparam = "EMAIL" "=" param-value 638 Description: This property parameter MAY be specified on "ORGANIZER" 639 or "ATTENDEE" properties. This property can be used in situations 640 where the calendar user address value of "ORGANIZER" and 641 "ATTENDEE" properties is not likely to be an identifier that 642 recipients of scheduling messages could use to match the calendar 643 user with, for example, an address book entry. The value of this 644 property is an email address that can easily be matched by 645 recipients. Recipients can also use this value as an alternative 646 means of contacting the calendar user via email. If a recipient's 647 calendar user agent allows the recipient to save contact 648 information based on the "ORGANIZER" or "ATTENDEE" properties, 649 those calendar user agents SHOULD use any "EMAIL" property 650 parameter value for the email address of the contact over any 651 mailto: calendar user address specified as the value of the 652 property. Calendar user agents SHOULD NOT include an "EMAIL" 653 property parameter when its value matches the calendar user 654 address specified as the value of the property. 656 Example: 658 ATTENDEE;CN=Cyrus Daboo;EMAIL=cyrus@example.com:mailto:opaque-toke 659 n-1234@example.com 661 6.3. FEATURE Property Parameter 663 Parameter Name: FEATURE 665 Purpose: To specify a feature or features of a conference or 666 broadcast system. 668 Format Definition: This property parameter is defined by the 669 following notation: 671 featureparam = "FEATURE" "=" featuretext *("," featuretext) 672 featuretext = ("AUDIO" / ; Audio capability 673 "CHAT" / ; Chat or instant messaging 674 "FEED" / ; Blog or Atom feed 675 "MODERATOR" / ; Moderator dial-in code 676 "PHONE" / ; Phone conference 677 "SCREEN" / ; Screen sharing 678 "VIDEO" / ; Video capability 679 x-name / ; Experimental type 680 iana-token) ; Other IANA registered type 682 Description: This property parameter MAY be specified on the 683 "CONFERENCE" property. Multiple values can be specified. The 684 "MODERATOR" value is used to indicate that the property value is 685 specific to the owner/initiator of the conference and contains a 686 URI that "activates" the system (e.g., a "moderator" access code 687 for a phone conference system that is different from the "regular" 688 access code). 690 Example: 692 CONFERENCE;VALUE=URI;FEATURE=AUDIO:rtsp://audio.example.com/ 693 event 694 CONFERENCE;VALUE=URI;FEATURE=AUDIO,VIDEO:http://video-chat.exam 695 ple.com/;group-id=1234 697 6.4. LABEL Property Parameter 699 Parameter Name: LABEL 701 Purpose: To provide a human readable label. 703 Format Definition: This property parameter is defined by the 704 following notation: 706 labelparam = "LABEL" "=" param-value 708 Description: This property parameter MAY be specified on the 709 "CONFERENCE" property. It is anticipated that other extensions to 710 iCalendar will re-use this property parameter on new properties 711 that they define. As a result, clients SHOULD expect to find this 712 property parameter present on many different properties. It 713 provides a human readable label that can be presented to calendar 714 users to allow them to discriminate between properties which might 715 be similar, or provide additional information for properties that 716 are not self-describing. 718 Example: 720 CONFERENCE;VALUE=URI;FEATURE=VIDEO; 721 LABEL="Web video chat, access code=76543"; 722 :http://video-chat.example.com/;group-id=1234 724 7. Security Considerations 726 Several of the new properties or parameters defined by this 727 specification allow reference to "external" URIs. Care MUST be taken 728 when accessing data at external URIs as malicious content could be 729 present. In addition, access to those URIs could be tracked, leading 730 to loss of privacy. 732 The "CONFERENCE" property can include a "FEATURE" property parameter 733 with a "MODERATOR" value. In some cases the access code used by the 734 owner/initiator of a conference might be private to an individual and 735 clients and servers MUST ensure that such properties are not sent to 736 attendees of a scheduled component, or sharees of a shared component. 738 8. IANA Considerations 740 8.1. Property Registrations 742 This document defines the following new iCalendar properties to be 743 added to the registry defined in Section 8.2.3 of [RFC5545]: 745 +------------------+---------+--------------------------------------+ 746 | Property | Status | Reference | 747 +------------------+---------+--------------------------------------+ 748 | NAME | Current | RFCXXXX, Section 5.1 | 749 | DESCRIPTION | Current | RFC5545 Section 3.8.1.5, RFCXXXX, | 750 | | | Section 5.2 | 751 | UID | Current | RFC5545 Section 3.8.4.7, RFCXXXX, | 752 | | | Section 5.3 | 753 | LAST-MODIFIED | Current | RFC5545 Section 3.8.7.3, RFCXXXX, | 754 | | | Section 5.4 | 755 | URL | Current | RFC5545 Section 3.8.4.6, RFCXXXX, | 756 | | | Section 5.5 | 757 | CATEGORIES | Current | RFC5545 Section 3.8.1.2, RFCXXXX, | 758 | | | Section 5.6 | 759 | REFRESH-INTERVAL | Current | RFCXXXX, Section 5.7 | 760 | SOURCE | Current | RFCXXXX, Section 5.8 | 761 | COLOR | Current | RFCXXXX, Section 5.9 | 762 | IMAGE | Current | RFCXXXX, Section 5.10 | 763 | CONFERENCE | Current | RFCXXXX, Section 5.11 | 764 +------------------+---------+--------------------------------------+ 766 8.2. Parameter Registrations 768 This document defines the following new iCalendar property parameters 769 to be added to the registry defined in Section 8.2.4 of [RFC5545]: 771 +--------------------+---------+----------------------+ 772 | Property Parameter | Status | Reference | 773 +--------------------+---------+----------------------+ 774 | DISPLAY | Current | RFCXXXX, Section 6.1 | 775 | EMAIL | Current | RFCXXXX, Section 6.2 | 776 | FEATURE | Current | RFCXXXX, Section 6.3 | 777 | LABEL | Current | RFCXXXX, Section 6.4 | 778 +--------------------+---------+----------------------+ 780 8.3. Display Types Registry 782 This document defines the following new iCalendar value registry as 783 per Section 8.2.6 of [RFC5545]: 785 +--------------+---------+----------------------+ 786 | Display Type | Status | Reference | 787 +--------------+---------+----------------------+ 788 | BADGE | Current | RFCXXXX, Section 6.1 | 789 | GRAPHIC | Current | RFCXXXX, Section 6.1 | 790 | FULLSIZE | Current | RFCXXXX, Section 6.1 | 791 | THUMBNAIL | Current | RFCXXXX, Section 6.1 | 792 +--------------+---------+----------------------+ 794 8.4. Feature Types Registry 796 This document defines the following new iCalendar value registry as 797 per Section 8.2.6 of [RFC5545]: 799 +--------------+---------+----------------------+ 800 | Feature Type | Status | Reference | 801 +--------------+---------+----------------------+ 802 | AUDIO | Current | RFCXXXX, Section 6.3 | 803 | CHAT | Current | RFCXXXX, Section 6.3 | 804 | FEED | Current | RFCXXXX, Section 6.3 | 805 | MODERATOR | Current | RFCXXXX, Section 6.3 | 806 | PHONE | Current | RFCXXXX, Section 6.3 | 807 | SCREEN | Current | RFCXXXX, Section 6.3 | 808 | VIDEO | Current | RFCXXXX, Section 6.3 | 809 +--------------+---------+----------------------+ 811 9. Acknowledgments 813 Thanks to the following for feedback: Bernard Desruisseaux, Mike 814 Douglass, Lucia Fedorova, Ken Murchison, Arnaud Quillaud, and Dave 815 Thewlis. This specification came about via discussions at the 816 Calendaring and Scheduling Consortium. 818 10. References 820 10.1. Normative References 822 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 823 Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/ 824 RFC2119, March 1997, 825 . 827 [RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax 828 Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/ 829 RFC5234, January 2008, 830 . 832 [RFC5545] Desruisseaux, B., Ed., "Internet Calendaring and 833 Scheduling Core Object Specification (iCalendar)", RFC 834 5545, DOI 10.17487/RFC5545, September 2009, 835 . 837 [W3C.REC-css3-color-20110607] 838 A‡elik, T., Lilley, C., and D. Baron, "CSS Color 839 Module Level 3", World Wide Web Consortium Recommendation 840 REC-css3-color-20110607, June 2011, 841 . 843 10.2. Informative References 845 [RFC2397] Masinter, L., "The "data" URL scheme", RFC 2397, DOI 846 10.17487/RFC2397, August 1998, 847 . 849 [RFC3966] Schulzrinne, H., "The tel URI for Telephone Numbers", RFC 850 3966, DOI 10.17487/RFC3966, December 2004, 851 . 853 [RFC5546] Daboo, C., Ed., "iCalendar Transport-Independent 854 Interoperability Protocol (iTIP)", RFC 5546, DOI 10.17487/ 855 RFC5546, December 2009, 856 . 858 [RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer 859 Protocol (HTTP/1.1): Message Syntax and Routing", RFC 860 7230, DOI 10.17487/RFC7230, June 2014, 861 . 863 Appendix A. Change History (To be removed by RFC Editor before 864 publication) 866 Changes in draft-ietf-calext-extensions-01: 868 1. Clarified difference between SOURCE and URL properties. 870 2. Use labelparam not infoparam. 872 Changes in draft-ietf-calext-extensions-00: 874 1. Document renamed after WG adoption. 876 2. Fixed tel: URI reference. 878 Changes in draft-daboo-icalendar-extensions-09: 880 1. Re-instated a trimmed down version of the CONFERENCE property 881 after serious interest expressed by implementors. 883 2. LABEL property used instead of INFO - appropriated from another 884 iCalendar draft. 886 Changes in draft-daboo-icalendar-extensions-08: 888 1. Trimmed down the display values to a minimal set. 890 Changes in draft-daboo-icalendar-extensions-07: 892 1. Removed ALTURI parameter - now use ALTREP. 894 2. Removed VALID property. 896 3. Removed TIMEZONE-ID property. 898 4. Added FULLSIZE and THUMBNAIL display values. 900 5. Added EMAIL property parameter. 902 6. Added LAST-MODIFIED property for use with VCALENDAR. 904 7. Added CATEGORIES property for use with VCALENDAR. 906 8. URL use now aligned with 5545. 908 9. Added SOURCE property. 910 10. COLOR now uses CSS3 values. 912 Changes in draft-daboo-icalendar-extensions-06: 914 1. Removed BROADCAST/CONFERENCE properties and related parameters. 916 Changes in draft-daboo-icalendar-extensions-05: 918 1. Added section with recommendation on handling extension 919 properties. 921 2. Added VALID property. 923 Changes in draft-daboo-icalendar-extensions-04: 925 1. TZID changed to new property TIMEZONE-ID. 927 2. Minor formal syntax changes. 929 Changes in draft-daboo-icalendar-extensions-03: 931 1. Dropped CALENDAR- prefix 933 2. DESCRIPTION, UID and TZID now based on existing RFC5545 934 properties 936 3. COLOR now on both the calendar and component level 938 4. IMAGE now on both the calendar and component level 940 5. Added FEATURE and REGION parameters to CONFERENCE property 942 6. Added ALTURI parameter to IMAGE property 944 7. Added FEED value to FEATURE parameter 946 8. Added BROADCAST property and clarified that CONFERENCE is for bi- 947 direction channels and BROADCAST is for uni-directional. 949 Changes in draft-daboo-icalendar-extensions-02: 951 1. Minor wording changes. 953 2. Interval is now described as the "minimum interval". 955 3. Added CONFERENCE property and INFO parameter. 957 Changes in draft-daboo-icalendar-extensions-01: 959 1. Fixed DISPLAY parameter handling of x- and iana tokens to state 960 that clients ignore the image if the token is not recognized. 962 2. Allow language variants for CALENDAR-NAME and CALENDAR- 963 DESCRIPTION. 965 3. Added registry for DISPLAY values. 967 Author's Address 968 Cyrus Daboo 969 Apple Inc. 970 1 Infinite Loop 971 Cupertino, CA 95014 972 USA 974 Email: cyrus@daboo.name 975 URI: http://www.apple.com/