What is ICS File Format?

ICS File

Brief on ICS File

A file format which provides facility to the web user for sending news of meetings and tasks to other Internet users is known as an iCalendar or an ICS file. In general, these files are having four extensions i.e, .ical, .ics, .ifb, and .icalendar. ICS file format is a type of the Exchange calendar data file format that is accessed and supported by various applications like Apple Calendar, Google Calendar, IBM Notes, Yahoo! Calendar, eM Client, etc. In addition, this file is also partially supported by Novell GroupWise and Microsoft Outlook. In this article, we will discuss about What is ICS file format with it’s different.

The ICS file extension is generated to transfer calendar data like events, appointments, meetings, etc., for sharing such data. This file includes detail like a description, time duration, location, etc.

MIME Type of ICS File Extension

The MIME type of ICS File Format is text/calendar, since it is a plain text file.

Detail Study of ICS File Format

This section is going to help forensics team to study What is ICS file format ?, which might be having details about any event, meetings, etc.

Core Object: This is the top-level component of iCalendar, which is a collection of calendar and scheduling data. This information comprises of an individual ICS object and several objects can also be gathered altogether.

  • icalbody: The entire content between BEGIN:VCALENDAR and END:VCALENDAR is considered as icalbody.
  • iCalendar: The second statement i.e., VERSION 2.0 denotes that data is present in iCalendar format. If this line is written as VERSION 1.0 then, it means that the data is in old format of vCalendar.
  • Calendar Body: This content of the file is made up of statements having properties and multiple elements of calendar in it. The properties are applied to an entire calendar and components are variety of calendar properties, which generates design of calendar schematic.
MHT File

Following are several types of elements, which could be implemented in a ICS file format:

Event(VEVENT): It is describing an event that is having a certain time duration on a calendar. In general, when a person enables any calendar event, this causes the time to be denoted as busy. Since it is for a particular time duration, therefore VEVENT may involve a VALARM, which provides an alarm feature. Such type of events are having a DTSTART that is having a starting time and a DTEND having ending time. Moreover, if this calendar event gets repeated then, DTSTART value is set initially.

what is ICS

VEVENT can also be used as calendar events, without any specific time like daily reminders or birthdays date. If a person wants to share cancellation of an event then, event UID should be same as original one, and properties should be set to cancel Ex.

In order to update a sending event, one needs to match UID with the original one and rest of the properties should be set as SEQUENCE: Num of Update. For example: for first update, write SEQUENCE:1. Furthermore, in Outlook the SUMMARY attribute is changed by the Subject part in the Appointment form and Description is to write details of entire appointment.

what is ICS

ICS File
ICS File

Busy/Free time (VFREEBUSY):

It is a request for free/busy time duration i.e., response to a request or a published set of busy time.

Other Types of Element:

Components like VTIMEZONE and VALARM are considered as sub-components of the calendar. In addition, whenever a scheduled event changes, UID field shares its update. When event is initiated a globally unique identifier is developed. In case of later event distribution with same UID, it substitutes with the original one.

ICS File

FAQs

Listed Commonly Asked Questions and Their Answers

Yes, you can convert ICS file in a portable document. You just need to print your iCal file in PDF format. Go to File -> Print -> Continue and then choose PDF option by clicking on Save As PDF file type.

Go through following set of instructions to open a ICS file extension in Microsoft Outlook:

  • Click on the link of iCal on a website
  • When a window is prompted click on Open button and then under Other Calendars section, view your iCalendar file.

In order to download calendar data from iCloud, users need to have credentials of Apple account and then follow the below mentioned steps:

  • In your iCloud account, open Calendar item
  • Share this calendar publicly and then copy the URL, which is for shared calendar and then paste it into address field of your web browser
  • Rename webcal to http and pres Enter/Return

Yes, there are following two ways by which you can perform the same:

  • One way is to open and view iCal on Google Calendar
  • Another is to use free utilities, which are available in market to view ICS file extension.

Conclusion

After understanding the need of ICS file extension for end users, we had covered all the aspects of iCalendar in this blog. The major attempt has been made for allowing one to easily learn What is ICS file and find out its importance of collecting data for performing digital forensics.