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 valuabl ...

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 (

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 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 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 ...

) 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 trees are cultivated worldwide and are the most widely grown species in the genus '' Malus''. The tree originated in Central Asia, where its wild ances ...

), 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 wor ...

), and Lisa Dusseault ( CommerceNet). ''CalDAV'' is designed for implementation by any collaborative software, 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 definitio ...

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 format, which allows the server to understand and process the data. Parsing the iCalendar 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
/ref> * iPhone (version 3.0 or version 2.1 with Remote Calendar) * CalDavZAP (Web-based HTML5 / JavaScript application, Open Source)CalDavZAP
/ref> * CalDAV Tasksync for

Android Android may refer to: Science and technology * Android (robot), a humanoid robot or synthetic organism designed to imitate a human * Android (operating system), Google's mobile operating system ** Bugdroid, a Google mascot sometimes referred to ...

TaskSync
/ref> * CalDAV-Sync for

CalDAV-Sync
/ref> * CalendarSync for

CalendarSync
/ref> * DAVx⁵ (previously called DAVdroid) for

(Open Source)DAVx⁵
/ref> *

EVO Collaborator for Outlook EVO or Evo may refer to: Companies * Evo (company), American sporting goods and outdoor recreation retailer Games * Evolution Championship Series, an annual fighting game esports tournament in the US * ''Evo'' (board game), a 2001 board game ...

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 ...

(Windows, macOS) * gSyncitFieldston Software
/ref> (Sync Microsoft Outlook with mobile/tablet device) * Horde GroupwareHorde Groupware
/ref> * iCal4OL (No longer available for new customers) * iCal/Calendar.app (Since Mac OS X Leopard !V 10.5) * iCal Import/Export CalDAV for

iCal Import/Export CalDAV
/ref> * Mailfence CalDAV client through iCAL/vCAL * Sunbird or Thunderbird with the

Lightning Lightning is a naturally occurring electrostatic discharge during which two electrically charged regions, both in the atmosphere or with one on the ground, temporarily neutralize themselves, causing the instantaneous release of an average ...

extension (Linux, Windows, Unix, Mac OS X) * OpenSync for

* Outlook CalDav Synchronizer (open source) adds CalDAV support to Microsoft OutlookOutlook CalDav Synchronizer
/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 ...

, though restricted to certain providers

Server

The list of CalDAV servers includes: *

Darwin Darwin may refer to: Common meanings * Charles Darwin (1809–1882), English naturalist and writer, best known as the originator of the theory of biological evolution by natural selection * Darwin, Northern Territory, a territorial capital city i ...

Calendar Server * Baïkal, a lightweight CalDAV and CardDAV server. * Bedework (former UWCalendar) *

Bynari Collaboration Suite Bynari is a defunct company based in Dallas, developing server and email software, mainly known for its Insight Family, similar to Microsoft Exchange Server with Outlook. Development of the products is a joint effort with various OEM partners. ...

* Chandler Server (Cosmo) * CommuniGate Pro Since version 5.2 * Cyrus IMAP server since version 2.4.17 * DAViCal * DPCalendar * DavMail * Daylite CalDAV Server *

Dingo Calendar Server The dingo (''Canis familiaris'', ''Canis familiaris dingo'', ''Canis dingo'', or ''Canis lupus dingo'') is an ancient (basal) lineage of dog found in Australia. Its taxonomic classification is debated as indicated by the variety of scientif ...

* EGroupware Since version 1.6 *

EVO Mail Server EVO or Evo may refer to: Companies * Evo (company), American sporting goods and outdoor recreation retailer Games * Evolution Championship Series, an annual fighting game esports tournament in the US * ''Evo'' (board game), a 2001 board game * ...

Fabasoft Folio Cloud Fabasoft Folio Cloud is a cloud computing service developed by Fabasoft in Linz, Austria announced in April 2010. It focuses on enabling secure collaboration and is web-based with iOS and Android apps for use on mobile devices. The software is ...

* Google Calendar * 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, ...

* MDaemon Email Server * Mailfence *

mod caldav Mod, MOD or mods may refer to: Places * Modesto City–County Airport, Stanislaus County, California, US Arts, entertainment, and media Music * Mods (band), a Norwegian rock band * M.O.D. (Method of Destruction), a band from New York City, US * ...

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 ...

* Open-Xchange * Oracle Beehive *

Oracle Siebel CRM 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 '' ...

* Oracle Communications Calendar Server * ownCloud * Radicale (CalDAV) * SOGo *

SabreDAV sabre/dav is an open source WebDAV server, developed by fruux and built in PHP. It is an implementation of the WebDAV protocol (with extensions for CalDAV and CardDAV), providing a native PHP server implementation which operates on Apache 2 and ...

* Scalix *

Sun Java Calendar Server The Sun Java System Calendar Server was Sun's calendar ( scheduling) server. The currently available version is 6.3 which is now part of the Sun Java System Communications Suite. Users can access their calendar and task list items using a variet ...

Synology Calendar
* Synovel CollabSuite * Xandikos *

Yahoo Calendar Yahoo Calendar is a Web-based calendar service from Yahoo!. It can read calendar feeds and events syndicated from sites that make use of the published Yahoo calendar programming interfaces. While users are not required to have a Yahoo Mail account ...

* Zarafa Since la version 6.30.0 * Zimbra Since version 4.5 * sync!Egw *

Zoho CRM Zoho Corporation is an Indian multinational technology company that makes computer software and web-based business tools. It is best known for the online office suite offering Zoho Office Suite. The company was founded in 1996 by Sridhar Vemb ...

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