secret splitting Algorithm: Assume Trent wishes to protect the message m Trent generates a random bit string r, the same length m Trent computes m=s Trent gives Alice r Trent gives Bob s Each of the pieces is called a shadow To reconstruct m, alice and bob xor their shadows together. If r is truly random the system is perfectly secure OTP) To extend the scheme to n people generate n random bit strings e. g.m⊕rs⊕t=u3 secret splitting Algorithm: Assume Trent wishes to protect the message m: Trent generates a random bit string r, the same length m. Trent computes m  r = s Trent gives Alice r Trent gives Bob s • Each of the pieces is called a shadow. • To reconstruct m, Alice and Bob XOR their shadows together. • If r is truly random, the system is perfectly secure (OTP). • To extend the scheme to n people, generate n random bit strings e.g. m  r  s  t = u