What does a DID actually name or identify?

[mwherman2000]

First, this is going to sound like a worn-out question that has been answered a million times.

Context

Suppose you have a cow with:

1. a yellow CCIA (Canadian Cattle Identification Agency) RFID button attached to the right ear (with its embedded globally unique identification number 124 000 123 456 789, for example)
2. a pink plastic ear tag with a handwritten "RCCL 205K 2013" on both sides of it using a special permanent marker attached to the left ear
3. a hot fire brand "R over C" on the Left Rib of the animal (i.e. my personal brand registered with the Alberta Livestock Identification Service (LIS))
4. brown white-face Hereford-crossbred cow with a healthy calf with the same features at her side
5. residing in Alberta Canada
6. that will live for 8-10 years (8-10 cow-calf cycles)

Assumptions

• Assume for this example, we're using DID Method did:cows.

Question

What is your cow's unique DID? What's the best answer?

[ankurdotb]

Depends on what did:cows specifies as its unique identifier in its system. Everything else is routing/resolution.