6. Authors' Addresses

   John Curran
   NSF Network Service Center (NNSC)
   10 Moulton Street
   Cambridge, MA 02138

   Phone: (617) 873-3400
   EMail: jcurran@nnsc.nsf.net

   April N. Marine
   SRI International
   Network Information Systems Center
   333 Ravenswood Avenue, EJ294
   Menlo Park, CA  94025-3493

   Phone: (415) 859-5318
   EMail: april@nisc.sri.com