PKI past, present and future 
Antonio Lioy, Marius Marian, Natalia Moltchanova, and Massimiliano Pala
 
International Journal of Information Security 
Issue Volume 5, Number 1 / January, 2006 
DOI 10.1007/s10207-005-0077-9 
Pages 18-29 

This paper discusses some design and management issues in running
an open PKI, based on the experience gained in the day-by-day operation of
the EuroPKI infrastructure. The problems are discussed with an historical
perspective that includes real-life lessons learnt in EuroPKI about
certification practices, services and applications. User-reported problems
are also discussed to identify problems that hamper large scale adoption of
public-key certificates. The article closes with a general outlook for the
field and the description of the future EuroPKI plans.