Introduce country identification helpers

[sthagen]

Similar to the identification of dataset from metadata precision issue, providing a text field to name a country for such essential constraints as processing/storage (dis-)allowed seems vague.

I understand, that this was the result of many prior D&ampTA internal discussion rounds, but still we can do better without adding barriers to producers / labelers that can not use fixed ISO country codes.

Introducing such country identification helper dimensions with the following properties in a someOf set should go a long way.

• 2-letter ISO code
• 3-letter ISO code
• freetext (the existing contributed field)

[davaya]

The 249 ISO country codes and subdivision codes (the UK has 222 subdivisions of various types, Germany has 17 lands) should be referenced by DPS. If a contributed freetext field cannot be mapped to a country and subdivision it could stand alone, but it's not clear what that would mean. If it does correspond directly to a country/subdivision but cannot be replaced by the standard English or French text then the freetext could be carried in addition to those.

The standard is pretty comprehensive; a couple of examples are available in https://github.com/oasis-tcs/dps/tree/contributed-dpkemp-information-model/contributions/dpkemp/geography. But if a freetext field needs to be added, with justification, then sure, why not.

[davaya]

In addition, the geographic -included and -excluded properties need to be mutually exclusive; it doesn't make sense to say something must be processed in {A, B, C} and must be processed anywhere but {X, Y, Z}. In firewall configurations there can be an entire hierarchy of allow and deny rules, and because it's hierarchical there must be a default (allow or deny) and an ordering below the default from most general to most specific.

Presumably DPS doesn't need that level of complexity, but it could have a whitelist or a blacklist but not both without more design effort.

[sthagen]

I thought about adding the option for producers to define named sets of countries, so that instances can define such sets under identifiers, and then simply refer to them, instead of always repeating the listings.

Not so sure, if the mathematical idea of either-or applies to (dis-)allow pairs when legal matters interfere. There can be two small distinct subsets of all countries for (dis-)allow and all the rest is left as an exercise for the consumer.