I propose to add some text to section 8 to explain that:

• Mandatory information is intended to allow the receiver of data to provide the best service; however, the sender may not always be able to provide the information for a particular mandatory property (e.g. a dataset might not have a dcat:landingPage which is proposed to be mandatory in the current draft)
• Minimal information describes the level of information below which exchange does not make sense (e.g. if a data set has no dct:description, the receiver would not be able to show its users what the dataset is about)

The proposed resolution is to add the following text to section 8:

Mandatory information is intended to allow the receiver of data to provide the best service; however, the sender may not always be able to provide the information for a particular mandatory property (e.g. a dataset might not have a dcat:landingPage which is proposed to be mandatory in the current draft)

Minimal information describes the level of information below which exchange does not make sense (e.g. if a data set has no dct:description, the receiver would not be able to show its users what the dataset is about)

Hi Makx, 

The difference between mandatory and minimal is not very clear.

If a property is mandatory, i.e. it is expected to exist, shouldn't be also considered to be part of the minimal set?

In my opinion the application profile should be as clear as possible. We can have a very limited set of mandatory properties (possibly coinciding with what we mean by minimal) and leave the others as optional.
It's an open world after all and people can decide themsevles which of the optional ones fit their purposes.
 

+1 that the differentiation is some what tricky understand.

Two ideas:

• link Minimal/Mandatory/Optional to MUST/SHOULD/MAY as in RFC2119.
• Put all properties in one table, so every one can see at first glance what must/should/may be in a piece of metadata.

This issue has been superseded by the changed approach in Draft 2 to distinguish mandatory, recommended and optional properties. There is no mention of minimum/minimal properties anymore.

Terms from RFC2119 are now being used.