CalDAV - What’s behind the network protocol?
The abbreviation CalDAV stands for "Calendar Distributed Authoring and Versioning”. CalDAV is a network protocol which was first submitted to the IETF (Internet Engineering Task Force) in 2003 for review and first specified in RFC 4791 in 2007. It allows calendar data exchange via WebDAV/HTTP and thereby access to your calendar from any device and the ability to sync it from anywhere. When you add new appointments or edit existing calendar entries, the adjustments are updated automatically on all synchronised devices - whether it’s a PC, smartphone or tablet.
How does CalDAV work?
CalDAV makes it possible to manage and edit appointments, events and time blocks on all devices, regardless of the platform. The protocol manages and distributes calendar events here through the transmission protocol primarily used in the Internet HTTP. All events published by CalDAV are presented in iCalendar format whereby each standard browser can display a downloaded appointment or event in its iCalendar.
The basis for the administration and synchronization is a WebDAV environment which, thanks to CalDAV, is also extended to include an access control and iCalendar evaluation functions. Furthermore, a write lock can be set up for other users, available appointments can be forwarded and parallel changes to an entry can be merged. This way, you can not only synchronise your calendar to multiple devices, but also share it with other users. If you would also like to synchronise your contact data, there is the protocol CardDAV.
In order to be able to use CalDAV, you must implement the network protocol in your calendar applications by downloading and installing a CalDAV client. You can then use this programme to create a connection to a CalDAV server which regulates the exchange of calendar data as a central instance.
What is a CalDAV client and what is a CalDAV server?
A CalDAV client is a computer programme which runs on a smartphone, tablet or PC, and communicates with a central computer - referred to as a server - via the CalDAV protocol and can thereby send and receive calendar data. In addition, the terminal itself is often referred to as a client. The client software must support not only the network protocol but also your device in order to achieve this. This is why, for example, there are different clients for Windows, Android, or Apple devices.
A CalDAV server acts as the counterpart to the CalDAV client: As a contact point for all requesting clients, it forms the basis for data exchange and therefore for the entire calendar synchronization. That means you need one CalDAV server to store your data, and an appropriate client on your device that can retrieve and display the data from the server.
Hosted Exchange with IONOS
The prefect solution for your business! Improve your productivity with the latest version of the world’s leading email and calendar solution hosted by IONOS!
The most important CalDAV servers and clients at a glance
Suitable clients for the synchronization of calendar data via CalDAV are, among others:
- CalendarSync for Android
- AgenDAV
- Evolution
- Atmail (from Version 6.0)
- Outlook CalDAV Synchroniser (free Outlook plug-in)
- iPhone
The iPhone is listed here as a client, as the device has a CalDAV-enabled calendar function from version 3.0 (or from version 2.1 with RemoteCalendar).
How to implement CalDAV
If you would like to set up your own CalDAV server, you would need a fixed IP address. Once the server is up and running, download the CalDAV client of your choice, install it and then create an account. Connect the profile to the server by specifying the relevant data such as the previously set network address. This is followed by fine adjustments where you specify the options you want - for example, who you want to share the calendar with.
Related articles
DHCP: What’s behind the Dynamic Host Configuration Protocol
If you’re connected to an internet router and power on your computer, it automatically obtains the necessary network parameters, such as the IP address, subnet mask, or DNS server. This is made possible by the Dynamic Host Configuration Protocol (DHCP), which simplifies address assignment when connecting to the internet and makes setting up local networks easy as pie.
IGMP (Internet Group Management Protocol)
Using multicast connections, data streams can be transferred to a large number of clients easily and in such a way that saves resources – provided that the accessing systems are part of the same multicast group. In IPv4 networks, the organisation and management of these groups is based on the Internet Group Management Protocol (IGMP), which was published as early as 1989. What exactly this…
RDVectorShutterstock Network time protocol (NTP): definition and functionality
Computer systems and applications use time stamps for communication purposes. Synchronous system times are highly important for these so-called temporal signatures to be of any use – especially for systems that exchange information via the internet. A protocol that has provided valuable assistance for decades is the network time protocol (NTP) – here is an introduction to NTP, as well as some…
How to sync google calendar with outlook
In order to keep track of important meetings, many people use their Outlook calendar. Meanwhile, Google Calendar has established itself as a viable alternative, especially among smartphone users. You can now sync Outlook with Google Calendar so that you don't lose track when using both calendars or accidentally plan two events on the same date. Ensure that you always have all of your appointments…
ICS files – sending and receiving calendar entries
You can quickly and easily exchange calendar information using a digital calendar. ICS files allow you to send and receive important calendar events. These files can also be opened in other programs such as Excel. You can even import them into Outlook and Thunderbird. Here, you’ll learn what an ICS file is.
