Electronic signature verification system, electronic signature device and verification device, electronic signature verification manner, electronic signature manner and verification manner, electronic signature program and verification program

摘要

P To provide an electronic signature-verifying method which decreases the number of elements which constitute an electronic signature, shortens the length of an electronic signature, decreases the amounts of information and communication and decreases the amount of computation when verification is made; and to provide a device therefor. PSOLUTION: A prime number is represented by q, and the groups of order numbers q are represented by GSB1/SB, GSB2/SBand GSBT/SB and e is represented by a bilinear map e: GSB1/SB× GSB2/SB→ GSBT/SB. Then, the electronic signature-verifying device computes X'= gSB2/SBSPx/SP, Y'= gSB2/SBSPy/SP, and Y=gSB1/SBSPy/SP, by using random numbers x and y, and gSB1/SBand gSB2/SBwhich are each the generation origins of the GSB1/SBand GSB2/SB and respectively, to generate a public key pk. Furthermore, the electronic signature-verifying device computes bSB1/SB=mSPry/SPYSPr/SP, bSB3/SB=mSPrxy/SPYSPrx/SPand bSB5/SB=gSB2/SBSPry/SPby using gSB1/SB, gSB2/SB, random numbers r, x and y and a plane sentence m to generate an electronic signature σ = (bSB1/SB, bSB3/SB and bSB5/SB). A verification device determines whether e (bSB1/SB and gSB2/SB) =e (mgSB1/SB and bSB5/SB) and e (bSB3/SB and gSB2/SB) =e (bSB1/SB and X') are each established, by using the public key pk and the electronic signature σ and the plane sentence m, to verify whether falsification is made. PCOPYRIGHT: (C)2010 and JPO& INPIT