This property specifies the text value that uniquely identifies the "VTIMEZONE" calendar component in the scope of an iCalendar object.
IANA and non-standard property parameters can be specified on this property.
This property MUST be specified in a "VTIMEZONE" calendar component.
This is the label by which a time zone calendar component is referenced by any iCalendar properties whose value type is either DATE-TIME or TIME and not intended to specify a UTC or a "floating" time. The presence of the SOLIDUS character as a prefix, indicates that this "TZID" represents an unique ID in a globally defined time zone registry (when such registry is defined).
Note: This document does not define a naming convention for time zone identifiers. Implementers may want to use the naming conventions defined in existing time zone specifications such as the public-domain TZ database [TZDB]. The specification of globally unique time zone identifiers is not addressed by this document and is left for future study.
This property is defined by the following notation:
tzid = "TZID" tzidpropparam ":" [tzidprefix] text CRLF
tzidpropparam = *(";" other-param)
;tzidprefix = "/" ; Defined previously. Just listed here for reader convenience.
The following are examples of non-globally unique time zone identifiers:
The following is an example of a fictitious globally unique time zone identifier: