John Kohl, B. Clifford Neuman,
The Kerberos Network Authentication Service
Abstract: This paper gives an overview and specification of Version 5 of the protocol for the Kerberos network authentication system Version 4, described elsewhere, is presently in production use at MIT's project Athena, and at other Internet sites.
Jennifer G. Steiner,
The Kerberos Network Authentication Service
Abstract: This DRAFT RFC describes the concepts and model upon which the Kerberos network authentication system is based. It also provides a specification of the protocols employed. The motivations, goals, assumptions, and rationale behind design decisions are treated cursorily; they are fully described elsewhere [refs]. The discussion is based on the Version 4 implementation of Kerberos, currently in use at Project Athena. The protocols are under review, and are not proposed as an Internet standard. Comments are encouraged.
Bill Bryant, Designing
an Authentication System: a Dialogue in Four Scenes
Abstract: This dialogue provides a fictitious account of the design of an open-network authentication system called "Charon." As the dialogue progresses, the characters Athena and Euripides discover the problems of security inherent in an open network environment. Each problem must be addressed in the design of Charon, and the design evolves accordingly. Athena and Euripides don't complete their work until the dialogue's close.
Bill Bryant, Jennifer G. Steiner, John Kohl,
Kerberos Installation Notes DRAFT
Abstract: The release consists of three parts. The first part consists of the core Kerberos system, which was developed at MIT and does not require additional licenses for us to distribute. Included in this part are the Kerberos authentication server, the Kerberos library, the ndbm database interface library, user programs, administration programs, manual pages, some applications which use Kerberos for authentication, and some utilities. The second part is the Data Encryption Standard (DES) library, which we are distributing only within the United States. The third part contains Kerberos modifications to Sun's NFS, which we distribute as ``context diffs'' to the Sun NFS source code. Its distribution is controlled to provide an accounting of who has retrieved the patches, so that Project Athena can comply with its agreements with Sun regarding distribution of these changes.
Kerberos Mailing List,
Kerberos Mailing Collection
Abstract: This is a Mailing collection from kerberos mailing list.
John Kohl, Clifford Neuman, Kerberos
Version 5 RFC
Abstract: This is the RFC for fifth revision of version 5 of the Kerberos Protocol. At this point, the protocol is fixed. There have been some changes since version 4.
John T. Kohl, B. Clifford Neuman, Theodore Y. Ts'o, The
Evolution of the Kerberos Authentication Service
Abstract: The Kerberos Authentication Service, developed at MIT, has been widely adopted by other organizations to identify clients of network services across an insecure network and to protect the privacy and integrity of communication with those services. While Version 4 was a step up from traditional security in networked systems, extensions were needed to allow its wider application in environments with different characteristics than that at MIT. This paper discusses some of the limitations of Version 4 of Kerberos and presents the solutions provided by Version 5.
Steven M. Bellovin,
Limitations of the Kerberos Authentication System
Abstract: The Kerberos authentication system, a part of MIT's Project Athena, has been adopted by other organizations. Despite Kerberos's many strengths, it has a number of limitations and some weaknesses. Some are due to specifics of the MIT environment; others represent deficiencies in the protocol design. We discuss a number of such problems, and present solutions to some of them. We also demonstrate how special purpose cryptographic hardware may be needed in some cases.
Don Davis, Ralph Swick,
Network Security via Private-Key Certificates
Abstract: This paper present some practical security protocols that use private-key encryption in the public-key style. The system combines a new notion private-key certificates, a simple key-translation protocol, and key-distribution. These certificates can be administrated and used much as public-key certificates are, so that users can communicate securely while sharing neither an encryption key nor network connection.
Bill Bryant, John Kohl, Kerberos
Operation Notes DRAFT
Abstract: These notes assume that you have used the Kerberos Installation Notes to build and install your Kerberos system. As in that document, we refer to the directory that contains the built Kerberos binaries as [OBJ_DIR].
S. P. Miller, B. C. Neuman, J. I. Schiller, J. H. Saltzer, Kerberos
Authentication and Authorization System
Abstract: This document describes the assumptions, short and long term goals, and system model for a network authentication system, named Kerberos, for the Athena environment. An appendix specifies the detailed design and protocols to support these goals, and a set of UNIX(UNIX is a trademark of AT&T Bell Laboratories.) manual pages, not included here, describes an implementation for Berkeley 4.3 UNIX of both user interface commands and also library interfaces for clients and servers. The next section of the technical plan, E.2.2, describes a set of network applications that use Kerberos for authentication.
B. Clifford Neuman, Jennifer G. Steiner,
Authentication of Unknown Entities on an Insecure Network of
Abstract: Kerberos is implemented as a server that runs on a secure machine, and a set of libraries that is used by client applications and services. The initial implementation uses DES for encryption, but encryption is supported in a separate module that is easily replaced. Kerberos has been in use at MIT for two years, and is currently in beta test at 18 sites across the country. At MIT, Kerberos supports more than 8,000 entities (users and servers) in three different realms. It is used for authentication in rsh, rcp, rlogin, Sun's Network File System, mail, bulletin boards, notification and administrative applications. In summary, Kerberos allows users to authenticate themselves to net work services without entering a password at every request, and without relying on less secure methods, such as the host-authenticated .rhost mechanism.
Jennifer G. Steiner, Clifford Neuman, Jeffrey I. Schiller, Kerberos:
An Authentication Service for Open Network Systems
Abstract: In an open network computing environment, a workstation cannot be trusted to identify its users correctly to network services. Kerberos provides an alternative approach whereby a trusted third-party authentication service is used to verify users' identities. This paper gives an overview of the Kerberos authentication model as implemented for MIT's Project Athena. It describes the protocols used by clients, servers, and Kerberos to achieve authentication. It also describes the management and replication of the database required. The views of Kerberos as seen by the user, programmer, and administrator are described. Finally, the role of Kerberos in the larger Athena picture is given, along with a list of applications that presently use Kerberos for user authentication. We describe the addition of Kerberos authentication to the Sun Network File System as a case study for integrating Kerberos with an existing application.
Don Davis, Ralph Swick, Workstation
Services and Kerberos Authentication at Project
Abstract: This document proposes solutions for two problems obstructing Project Athena's implementation of workstation services. The principal problem is that workstation services demand a more flexible mutual authentication protocol than Kerberos currently provides. The egregious X access-control hack, xhost, for example, has lack of authentication as its root cause. This protocol weakness is also the reason that public workstations can't accept authenticated connections from rlogin, rcp, rsh, etc. We propose an extension to the Kerberos Ticket Granting Service protocol, that cleanly supports user-to-user mutual authentication. Our second proposal addresses the problem of ticket propagation. Currently, if a user wants tickets that are valid on a remote host, he has to run kinit in an encrypted rlogin session, unless he's willing to send his password in clear text. As an example of the use of our protocol extension, we describe a Kerberos application that would support a limited facility for secure ticket-propagation.
Kerberos Version 5 Slides
Abstract: This is a set of slides for Kerberos Version 5.
Built by Mark Crosbie and Ivan Krsul.
Security Archive Homepage.
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