Identifying the customer
Identifying customers, just like any other data record, requires understanding two important concepts. The first is unique identifiers (IDs) that point to that record and the second is the scope in which that ID is unique.
Some IDs, most notably universally unique identifiers (UUIDs), are unique across all systems for all time. Statistically speaking, the same ID will never be generated twice. Other IDs, such as an order number that increments each time an order is placed, are only unique within the scope of a particular commerce site or organization.
These IDs are particularly important because the integration options for each product require their own internal IDs. That means each system must know the appropriate ID for the systems it needs to update or retrieve a record from to do so efficiently.
The following table shows the required customer identifiers for each of the three component systems discussed so far:
