Basic summary or project title

Which components does it relate to? (e.g. XMLUI, JSPUI, Solr, SWORD, API, etc)

More detailed description with any relevant links to past/current work

If you think you might be willing to mentor it, add your name!

Stop Using Email as User Identifier

EPerson
AuthenticationManager

Use of email address as a persistent identifier for the DSpace conflicts with the fact that email addresses are not persistent. Email addresses go away and/or are reassigned to other individuals. There are also policy concerns with Authenticators like Shibboleth and CAS that may or may not deliver an email address as a organizational policy.  
This Task is a placeholder to identify a solution to correct for the problem.  
1.) DSpace should use a different identifier / key for the EPerson (netid? or combination of "authenticator + netID")  
2.) DSpace should make providing an email address as optional for cases where the Authentication features lack this specific capability.  
3.) Issuing emails should be optional for accounts without email addresses.  
4.) Stop storing email address (or any other detail about who made the change) in dc.description.provenance field.  
One proposed solution to this problem is that the Authentication Method should be broken off of EPerson and stored separately, making EPerson a "Profile" and the method of Authentication be stored separately (Password, Certificate, LDAP, Shibboleth, CAS, Facebook, Google) Different AuthenticationMethods may store the data as they see fit. And the Profile would store only those local details for that user.  
See for more detail: https://jira.duraspace.org/browse/DS-937?focusedCommentId=24361#comment-24361