V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

PPN
       Project Programmer Number


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

PPN
       Public Packet Switching


The Free On-line Dictionary of Computing (30 December 2018):

PPN

   Project-Programmer Number.

   A user-ID under TOPS-10 and its various mutant progeny at
   SAIL, BBN, CompuServe and elsewhere.  Old-time hackers
   from the PDP-10 era sometimes use this to refer to user IDs
   on other systems as well.

   [Jargon File]

   (1994-11-18)