Oracle Unified Directory - Use entryUUID on the client side to act as unique pointer to an entry

We have a requirement to generate a globally unique synthetic value for an attribute. The plan is to use this value as part of an access token provided to third party systems. This can act as a pointer to a specific user entry without revealing any further details about the user. We are thinking of a couple of options to achieve this:

1. Use the entryUUID operational attribute. Can think of the following potential problems with this:
   1. Creates a dependency on an internal operational attribute.
   2. Not sure if this will work consistently in a replicated topology. We did check for a couple of entries in a replicated topology consisting of 4 DS and the entryUUID value is indeed the same for the same entry in all DS instances – so this doesn’t seem to a problem unless there are certain special conditions under which the same entry can have different entryUUIDs in different nodes of a replicated topology.