PIN login is used with a SIP or Bizphone application. Logging in with PIN before dialing from those 2 applications would offer you a trace to see who made that call.
Manage PIN of a member
In order to add and check a PIN of a member, go to Home > Members > View a member > PIN
Go to Home > Members and view a member
At PIN section, click View
If the user does not have any PIN yet, help him to create one
If the user already has a PIN, you can give him the current PIN or reset it.
Auto generate PIN when importing a list of members
At Members > Import/Export members > Choose the option Auto create PIN for the imported members.