信息安全的关键——在于确切地了解谁正在访问您的最机密的网络信息资产——即系统用户的身份认证。一个突出的事实是许多最具危害性的犯罪都是饶过密码保护,通过窃取对信息或资金的访问权限来实施的。简单的“用户名+口令”的单因素身份认证方式已经远远不能满足很多系统的安全性要求,所以在安全性要求较高的网络系统中应该考虑采用在单一记忆因素(固定口 The key to information security - is to know exactly who is accessing your most secret network information asset - the authentication of the system user. One salient fact is that many of the most pernicious crimes are forgiven by password-protection, by stealing access to information or money. Simple “username + password” single factor authentication is far from satisfying the security requirements of many systems. Therefore, in a network system with higher security requirements, a single memory factor (fixed port