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== Format ==
A CRID is specified much like URLs. In fact, a CRID is a so-called [[uniform resource identifier|URI]]. Typically, the content creator, the broadcaster or a third party will use their [[___domain name system|DNS]]-names in a combination with a product-specific name to create globally unique CRIDs. That is, the syntax of a CRID is:
<
crid://authority/data
</syntaxhighlight>
The ''authority'' field represents the entity that created the CRID and its format is that of a DNS name. The ''data'' field represents a string of characters that will unambiguously identify the content within the authority scope (it is a string of characters assigned by the authority itself).
As an example, let's assume that [[BBC]] wanted to make a CRID for (all the programs of) the Olympics in China. It may have looked something like this
<
crid://bbc.co.uk/olympics/2008/
</syntaxhighlight>
This would be a group CRID, that is, a CRID representing a group of contents. Then, to refer to a specific event – such as the women's shot-put final – they could have used the following inside their metadata.
<
crid://bbc.co.uk/olympics/2008/final/shotput/women
</syntaxhighlight>
Currently,{{When|date=January 2013}} four types of CRIDs are playing a major role in some [[Unidirectional networks|unidirectional]] television networks: programme CRID, series CRID, group CRID, and recommendation CRID. One of the most important applications of CRIDs is the so-called series link recording function (SL) of modern digital video recorders ([[Digital video recorder|DVR]], [[Personal video recorder|PVR]]).
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The locators' format, as established in TV-Anytime, is quite generic and simple, and corresponds to:
<
[transport-mechanism]:[specific-data]
</syntaxhighlight>
The first part of the locator’s format (the transport mechanism) must be a string of characters that is unique for each mechanism (transport stream, local file, HTTP Internet access…). The second part must be unambiguous only within the scope of a given transport mechanism and will be standardized by the organism in charge of the regulation of the mechanism itself.
For instance, a DVB locator to identify a content within the transport stream of networks that follow this standard would be:
<
dvb://112.4a2.5ec;2d22~20121212T220000Z—PT01H30M
</syntaxhighlight>
which would indicate a content (identified by the string “2d22”) that airs on a channel available on a DVB network identified by the address “112.4a2.5ec” (network “112”, transport stream “4a2” and service “5ec”), on 12 December 2012 at 10 p.m. and with a duration of 90 minutes.
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