GlobalPlatform Put-Key and Key Versions
843851Aug 14 2006 — edited Oct 5 2006I want to change the default ISD keys of a JCOP card from 4041.. to someother value. My expectation was that the put-key command replaces these keys. However, I have some suprising findings:
1. Put-Key actually creates a new version of the keys.
2. All key versions allow you to mutually authenticate. I fail to understand why would someone like to have different keys to open the same lock. What is the reason behind this scheme?
3. It is not possible to change keyset 255, as in 255/1/404142...
4. You can have at the max four versions of the keys. Why limit on 4?
I am using JCOP31/JCOP41 cards.
I am very confused on the 2nd point. How do I change the default ISD keys?