Abstract: This article discusses the requirements for portable electronic devices with cryptographic capabilities to perform very secure network authentication, fare collection, vending system regulation, etc. It also shows how the DS1963S or DS1961S iButtons® meet these requirements, such as secret protection, "Zero Knowledge Proof", and secure challenge-response through the secure hash algorithm (SHA-1). Maxim > App Notes > 1-Wire DEVICES Keywords: secure network, authentication, fare collection, vending, secret protection, secrets, secure hash Oct 21, 2002 algorithm, SHA, SHA-1, DS1963S, DS1961S, cryptography, cryptographic, challenge response, SHA1 APPLICATION NOTE 1770 Securing Electronic Transactions Using SHA-1 Secure Hash Algorithm Abstract: This article discusses the requirements for portable electronic devices with cryptographic capabilities to perform very secure network authentication, fare collection, vending system regulation, etc. It also shows how the DS1963S or DS1961S iButtons meet these requirements, such as secret protection, "Zero Knowledge Proof", and secure challenge-response through the secure hash algorithm (SHA-1). Increasingly, the world is turning to portab……