Calendaring Extensions to WebDAV, or CalDAV, is an
Internet standard
In computer network engineering, an Internet Standard is a normative specification of a technology or methodology applicable to the Internet. Internet Standards are created and published by the Internet Engineering Task Force (IETF). They allow ...
allowing a
client
Client(s) or The Client may refer to:
* Client (business)
* Client (computing), hardware or software that accesses a remote service on another computer
* Customer or client, a recipient of goods or services in return for monetary or other valuable ...
to access and manage calendar data along with the ability to schedule meetings with users on the same or on remote
servers.
It lets multiple users in different locations to share, search and synchronize calendar data.
It extends the
WebDAV
WebDAV (Web Distributed Authoring and Versioning) is a set of extensions to the Hypertext Transfer Protocol (HTTP), which allows user agents to collaboratively author contents ''directly'' in an HTTP web server by providing facilities for concu ...
(
HTTP
The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, ...
-based protocol for data manipulation) specification and uses the
iCalendar
The Internet Calendaring and Scheduling Core Object Specification (iCalendar) is a media type which allows users to store and exchange calendaring and scheduling information such as events, to-dos, journal entries, and free/busy information, a ...
format for the calendar data.
The access protocol is defined by .
Extensions to CalDAV for scheduling are standardized as .
The protocol is used by many important open-source applications.
History
The ''CalDAV'' specification was first published in 2003 as an
Internet Draft
An Internet Draft (I-D) is a document published by the Internet Engineering Task Force (IETF) containing preliminary technical specifications, results of networking-related research, or other technical information. Often, Internet Drafts are int ...
submitted to the Internet Engineering Task Force (
IETF
The Internet Engineering Task Force (IETF) is a standards organization for the Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and a ...
) by Lisa Dusseault. In March 2007, the ''CalDAV'' specification was finished and published by the IETF as RFC 4791, authored by Cyrus Daboo (
Apple
An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple fruit tree, trees are agriculture, cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, wh ...
), Bernard Desruissaux (
Oracle
An oracle is a person or agency considered to provide wise and insightful counsel or prophetic predictions, most notably including precognition of the future, inspired by deities. As such, it is a form of divination.
Description
The word '' ...
), and Lisa Dusseault (
CommerceNet CommerceNet is a 501(c)6 organization established in 1994 to promote electronic commerce on the Internet. The organisation initially focused on industry-wide research and programs that have advanced the commercial use of the Internet.
History
Comm ...
). ''CalDAV'' is designed for implementation by any
collaborative software
Collaborative software or groupware is application software designed to help people working on a common task to attain their goals. One of the earliest definitions of groupware is "intentional group processes plus software to support them".
As re ...
, client or server, that needs to maintain, access or share collections of events. It is developed as an
open standard
An open standard is a standard that is openly accessible and usable by anyone. It is also a prerequisite to use open license, non-discrimination and extensibility. Typically, anybody can participate in the development. There is no single definition ...
to foster interoperability between software from different implementers.
Specification
The architecture of ''CalDAV'' (partially inherited from the underlying specifications) organizes the data (events, tasks, free-busy info, notes) in directories (collections), where multiple items (resources) reside. The resources and collections can be accessed by one or more users, using standard HTTP and DAV semantics to detect conflicting changes, or to provide locking.
For access control the concept of
ACLs are used, so each operation (view, edit, delete etc.) can be denied or granted per user. Therefore, the specification requires that CalDAV servers must support "WebDAV Access Control Protocol" (RFC 3744).
The calendar resources must use
iCalendar
The Internet Calendaring and Scheduling Core Object Specification (iCalendar) is a media type which allows users to store and exchange calendaring and scheduling information such as events, to-dos, journal entries, and free/busy information, a ...
format, which allows the server to understand and process the data. Parsing the
iCalendar
The Internet Calendaring and Scheduling Core Object Specification (iCalendar) is a media type which allows users to store and exchange calendaring and scheduling information such as events, to-dos, journal entries, and free/busy information, a ...
items is necessary, because the server has to support a number of calendaring-specific operations such as doing free-busy time reports and expansion of recurring events. With this functionality, a user may synchronize their own calendar to a CalDAV server, and share it among multiple devices or with other users. The protocol also supports non-personal calendars, such as calendars for sites or organizations.
Software
Client
The list of CalDAV clients includes:
*
AgenDAV (Open Source multi-language CalDAV WebClient with AJAX interface)
*
Bloben (Open Source self hosted CalDAV web client)
[Bloben](_blank)
/ref>
* iPhone (version 3.0 or version 2.1 with Remote Calendar)
* CalDavZAP (Web-based HTML5 / JavaScript application, Open Source)[CalDavZAP](_blank)
/ref>
* CalDAV Tasksync for Android[TaskSync](_blank)
/ref>
* CalDAV-Sync for Android[CalDAV-Sync](_blank)
/ref>
* CalendarSync for Android[CalendarSync](_blank)
/ref>
* DAVx⁵ (previously called DAVdroid) for Android (Open Source)[DAVx⁵](_blank)
/ref>
* EVO Collaborator for Outlook add caldav sync capability to Outlook
* Evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
(Linux, Unix, Windows)
* eM Client
eM Client is a Windows and macOS based email client for sending and receiving emails, managing calendars, tasks, contacts, and notes. Live chat is integrated as well. It was developed as a user-friendly alternative to existing email clients and c ...
(Windows, macOS)
* gSyncit[Fieldston Software](_blank)
/ref> (Sync Microsoft Outlook with mobile/tablet device)
* Horde Groupware[Horde Groupware](_blank)
/ref>
* iCal4OL (No longer available for new customers)
* iCal
Calendar is a personal calendar app made by Apple Inc. that runs on both the macOS desktop operating system and the iOS mobile operating system. It offers online cloud backup of calendars using Apple's iCloud service, or can synchronize with ...
/Calendar.app (Since Mac OS X Leopard !V 10.5)
* iCal Import/Export CalDAV for Android[iCal Import/Export CalDAV](_blank)
/ref>
* Mailfence
Mailfence is an encrypted email service that offers OpenPGP based end-to-end encryption and digital signatures. It was launched in November 2013 by ContactOffice Group, which has been operating an online collaboration suite for universities and ...
CalDAV client through iCAL/vCAL
* Sunbird
Sunbirds and spiderhunters make up the family Nectariniidae of passerine birds. They are small, slender passerines from the Old World, usually with downward-curved bills. Many are brightly coloured, often with iridescent feathers, particularly i ...
or Thunderbird
Thunderbird, thunder bird or thunderbirds may refer to:
* Thunderbird (mythology), a legendary creature in certain North American indigenous peoples' history and culture
* Ford Thunderbird, a car
Birds
* Dromornithidae, extinct flightless birds ...
with the Lightning
Lightning is a naturally occurring electrostatic discharge during which two electric charge, electrically charged regions, both in the atmosphere or with one on the land, ground, temporarily neutralize themselves, causing the instantaneous ...
extension (Linux, Windows, Unix, Mac OS X)
* OpenSync for Android
* Outlook CalDav Synchronizer (open source) adds CalDAV support to Microsoft Outlook[Outlook CalDav Synchronizer](_blank)
/ref>
* vdirsyncer synchronizes calendars (and addressbooks) between two storages, e. g. CalDAV (CardDAV) server with a local folder or file.
* Windows 10
Windows 10 is a major release of Microsoft's Windows NT operating system. It is the direct successor to Windows 8.1, which was released nearly two years earlier. It was released to manufacturing on July 15, 2015, and later to retail on J ...
, though restricted to certain providers
Server
The list of CalDAV servers includes:
* Apple
An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple fruit tree, trees are agriculture, cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, wh ...
Darwin Calendar Server
* Baïkal, a lightweight CalDAV and CardDAV server.
* Bedework (former UWCalendar)
* Bynari Collaboration Suite
* Chandler Server (Cosmo)
* CommuniGate Pro
CommuniGate Pro (CGatePro) is a highly scalable carrier grade unified communications server, as well as a development platform. The system is Internet Protocol based. The server is a single process, multi-threaded application written entirely in ...
Since version 5.2
* Cyrus IMAP server
The Cyrus IMAP server is electronic mail server software developed by Carnegie Mellon University. It differs from other Internet Message Access Protocol (IMAP) server implementations in that it is generally intended to be run on sealed servers, ...
since version 2.4.17
* DAViCal
DAViCal is a server for calendar sharing. It is an implementation of the CalDAV protocol which is designed for storing calendaring resources on a remote shared server. Although the events are stored in a SQL database the information between client ...
* DPCalendar
* DavMail
* Daylite CalDAV Server
* Dingo Calendar Server
* EGroupware Since version 1.6
* EVO Mail Server
* Fabasoft Folio Cloud
* Google Calendar
Google Calendar is a time-management and scheduling calendar service developed by Google. It became available in beta release April 13, 2006, and in general release in July 2009, on the web and as mobile apps for the Android and iOS platforms.
...
* Horde Groupware
* Icewarp-E-Mail-Server Since version 8.x
* Kerio Connect
Kerio Technologies, Inc. is a former technology company specializing in collaboration software and unified threat management for small and medium organizations. Founded in 2001, Kerio is headquartered in San Jose, California. In January 2017, GFI ...
* MDaemon Email Server
* Mailfence
Mailfence is an encrypted email service that offers OpenPGP based end-to-end encryption and digital signatures. It was launched in November 2013 by ContactOffice Group, which has been operating an online collaboration suite for universities and ...
* mod caldav
* Nextcloud
Nextcloud is a suite of client-server software for creating and using file hosting services. Nextcloud provides functionally similar to Dropbox, Office 365 or Google Drive when used with integrated office suite solutions Collabora Online or Only ...
* Open-Xchange
Open-Xchange is a web-based communication, collaboration and office productivity software suite, which enables full integration of email, documents, scheduling and social media.
History
Founded in 2005 by Rafael Laguna and Frank Hoberg, the softw ...
* Oracle Beehive
Oracle Beehive is collaboration platform software developed by Oracle Corporation that combines email, team collaboration, instant messaging, and conferencing in a single solution. It can be deployed on-premises as licensed software or subscribed ...
* Oracle Siebel CRM
* Oracle Communications Calendar Server
* ownCloud
ownCloud is an open-source software product for sharing and syncing of files in distributed and federated enterprise scenarios. It allows companies and remote end-users to organize their documents on servers, computers and mobile devices and w ...
* Radicale (CalDAV)
* SOGo
* SabreDAV
* Scalix
Scalix is an e-mail and groupware server that runs on Linux, licensed under the Scalix Public License (SPL).
The software provides e-mail, group calendaring and other collaborative software, which are standard in groupware. It can be also be ac ...
* Sun Java Calendar Server
Synology Calendar
* Synovel CollabSuite
* Xandikos
* Yahoo Calendar
* Zarafa Since la version 6.30.0
* Zimbra
Zimbra Collaboration, formerly known as the Zimbra Collaboration Suite (ZCS) before 2019, is a collaborative software suite that includes an email server and a web client.
Zimbra was initially developed by LiquidSys, which changed their name ...
Since version 4.5
* sync!Egw
* Zoho CRM
See also
* Exchange ActiveSync
Exchange ActiveSync (commonly known as EAS) is a proprietary protocol designed for the synchronization of email, contacts, calendar, tasks, and notes from a messaging server to a smartphone or other mobile devices. The protocol also provides mobi ...
* Comparison of CalDAV and CardDAV implementations
* Calendar
A calendar is a system of organizing days. This is done by giving names to periods of time, typically days, weeks, months and years. A date is the designation of a single and specific day within such a system. A calendar is also a physi ...
* CardDAV
vCard Extensions to WebDAV (CardDAV) is an address book client/server protocol designed to allow users to access and share contact data on a server.
The CardDAV protocol was developed by the IETF and was published as in August 2011. CardDAV is ...
* GroupDAV, an effort to create a simplified, straightforward protocol for calendars as well as contacts.
* iCalendar
The Internet Calendaring and Scheduling Core Object Specification (iCalendar) is a media type which allows users to store and exchange calendaring and scheduling information such as events, to-dos, journal entries, and free/busy information, a ...
* Scheduling OSID defines a software interface abstraction for calendaring protocols
* SyncML
SyncML (Synchronization Markup Language) is the former name for a platform-independent information synchronization standard. The project is currently referred to as ''Open Mobile Alliance Data Synchronization and Device Management''. The purpose o ...
* vCalendar
The Internet Calendaring and Scheduling Core Object Specification (iCalendar) is a media type which allows users to store and exchange calendaring and scheduling information such as events, to-dos, journal entries, and free/busy information, a ...
* WebDAV
WebDAV (Web Distributed Authoring and Versioning) is a set of extensions to the Hypertext Transfer Protocol (HTTP), which allows user agents to collaboratively author contents ''directly'' in an HTTP web server by providing facilities for concu ...
References
External links
CalDAV Resource Site
CalConnect, The Calendaring and Scheduling Consortium
WebDAV Resources
Open Calendar Sharing and Scheduling with CalDAV
L. Dusseault, J. Whitehead, IEEE Internet Computing 9(2)
RFCs
* – HTTP
* – WebDAV Access Control Protocol
* – CalDAV
* – WebDAV
* – iCalendar
* – iTIP
{{DEFAULTSORT:Caldav
Application layer protocols
Calendaring standards