why q|(p-1) in DLP protocols

Hi professors... I'm a student studying cryptography and e-cash. I've been wondering, why many cryptographic protocols based on discrete log problem such as Schnorr, Brand's e-cash, Chaum & Pedersen's DLP blind signature, etc, we must choose a prime q & p where q divides (p-1)? q is the exponenti

Re: Debit card fraud in Canada

-Original Message- From: Steve Reid <[EMAIL PROTECTED]> Date: Tuesday, 14 December, 1999 5:34 AM Subject: Re: Debit card fraud in Canada > >I'm not sure if I'd trust a smartcard-based system that didn't require >on-line connectivity. From what little I've seen such things usually >(alway

milis or newsgroup on financial crypto

Hello, Does anybody know any mailing list or newsgroup for people whose interested in financial cryptography, especially e-cash? Sincerely, -mukti Check out my homepage: www.geocities.com/SiliconValley/8972 > biodata, resumes, hobby, words of wisdom

financial crypto - like conferences

Hi... I need to know, whether any of you know any other financial-crypto-like international conferences at the second half of this year. I want to submit several of my papers, and I can't wait for FC 2001. The conference need not to be very theorethical or very prestigious, preferably a little bi

proxy signatures

Hi... I'm a research student studying crypto (newbies). I really need a paper, which I can not get: Masahiro Mambo, Usada & Eiji Okamoto "Proxy Signatures" Proceedings of the 1995 Symposium on Cryptography and Information Security (SCIS 95), Inuyama, Japan, 24-27 Jan 1995. I've mailed two of th

time dependant

Hi, I want to know whether there is a crypto building block which doesn't allow someone to open an encrypted message before a certain date. [Damn hard. Math functions don't grok "date". The only reasonable way to do this without a trusted third party is to pick an encryption algorithm that will

Re: CA cert chaining + 128 bit

-Original Message- From: ericm <[EMAIL PROTECTED]> To: Kick Willemse <[EMAIL PROTECTED]> Cc: codepunks <[EMAIL PROTECTED]>; crypto <[EMAIL PROTECTED]> Date: Friday, 24 March, 2000 12:58 AM Subject: Re: CA cert chaining + 128 bit >Automatically importing a root ca cert into the trusted ce

wiskey + cybertrust

Hi all: I have a question regarding WISEkey and another about Cybertrust. I know I can ask "them", but I just want to hear comments from the other Netters. 1. Cybertrust ~ I know that most browsers have (formerly GTE) Cybertrust root CA. Suppose I am a CA and my certificate is signed