Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

This document presents a framework to assist the writers of certificate policies or certification practice statements for certification authorities and public key infrastructures. In particular, the framework provides a comprehensive list of topics that potentially (at the writer's discretion) need to be covered in a certificate policy definition or a certification practice statement.

A roaming user, who accesses a network from different client terminals, can be supported by a credentials server that authenticates the user by password then assists in launching a secure environment for the user. However, traditional credentials server designs are vulnerable to exhaustive password guessing attack at the server. We describe a new credentials server model and supporting protocol that overcomes that deficiency. The protocol provides for securely generating a strong secret from a weak secret (password), based on communications exchanges with two or more independent servers. The result can be leveraged in various ways, for example, the strong secret can be used to decrypt an encrypted private key or it can be used in strongly authenticating to an application server. The protocol has the properties that a would-be attacker cannot feasibly compute the strong secret and has only a limited opportunity to guess the password, even i f he or she has access to all messages and has control over some, but not all, of the servers.

To build effective public-key infrastructures, well-entrenched standards are essential because many different applications and different vendor products need to be supported and used. Standards for public-key certificate and certificate revocation list (CRL) formats are most important. The recognized standard in this area is ITU-T X.509, first published in 1988. In 1993, the Internet Privacy Enhanced Mail (PEM) proposals refined the use of X.509. However, more recently it has become apparent that there are several deficiencies in the X.509 formats and in the PEM refinements. Consequently, standards groups have undertaken an expedited activity to revise the X.509 formats by adding extensibility mechanisms and defining a set of standard extensions to satisfy a range of recognized needs. This paper outlines the status of this work as of mid-1995.