BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Bounds on proof size and distributive encryption - R. Ramanujam\, 
 Institute of Mathematical Sciences\, Chennai
DTSTART:20120608T130000Z
DTEND:20120608T140000Z
UID:TALK38461@talks.cam.ac.uk
CONTACT:Bjarki Holm
DESCRIPTION:In the formal analysis of security protocols\, what the intrud
 er infers from messages travelling on the network can be abstracted into c
 hecking whether a term is derivable in an inference system from a given fi
 nite set of terms (subject to some equations). This is typically in polyno
 mial time but when encryption is distributive over one of the other operat
 ors\, it gets difficult: we show that the problem is DEXPTIME-complete by 
 obtaining bounds on proof size. This is to be contrasted with distributive
  encryption in the presence of an abelian group operator where only a non-
 elementary upper bound is known.\n
LOCATION:Room FW26\, Computer Laboratory\, William Gates Building
END:VEVENT
END:VCALENDAR