37 research outputs found
Heimdal and Windows 2000 Kerberos - how to get them to play together
No full textAs a practical means of achieving better security and single sign-on, the Kerberos network authentication system has been in wide use in the Unix world for many years.
Microsoft has included its own implementation in Windows 2000, replacing the NTLM authentication system from older Windows NT versions. This facilitates sharing account information between Unix and Windows machines, as there is no need to keep different passwords.
Although Microsoft's Kerberos implementation mostly follows the specification, there are a number of deviations and extensions, not all of which are well documented. Consequently, it is not always obvious how to fit Windows 2000 clients and servers into an existing Kerberos environment. In this paper we discuss the differences between the two systems and describe how we got our Kerberos implementation, Heimdal, to work with Windows 2000
A Freely Available Scalable MTA
No full textRights to individual papers remain with the author or the author's employer. Permission is granted for noncommercial reproduction of the work for educational or research purposes. This copyright notice must be included in the reproduced paper. USENIX acknowledges all trademarks herein. For more information about the USENIX Association
Heimdal and Windows 2000 Kerberos - how to get them to play together
No full textAs a practical means of achieving better security and single sign-on, the Kerberos network authentication system has been in wide use in the Unix world for many years. Microsoft has included its own implementation in Windows 2000, replacing the NTLM authentication system from older Windows NT versions. This facilitates sharing account information between Unix and Windows machines, as there is no need to keep different passwords. Although Microsoft's Kerberos implementation mostly follows the specification, there are a number of deviations and extensions, not all of which are well documented. Consequently, it is not always obvious how to fit Windows 2000 clients and servers into an existing Kerberos environment. In this paper we discuss the differences between the two systems and describe how we got our Kerberos implementation, Heimdal, to work with Windows 2000.</p
Different database methods in Heimdal
No full textThis paper describes some of the common ways of implementing the Kerberos database and distributing this among the Kerberos servers. The methods available in the Heimdal implementations are examined and some performance measurements are presented.
An essay on economic reforms and social change in China
No full textThe author applies a systems-oriented"holistic"approach to China's radical economic reforms during the past quarter of a century. He characterizes China's economic reforms in terms of a multidimensional classification of economic systems. When looking at the economic consequences of China's change of economic system, he deals with both the impressive growth performance and its economic costs. The author also studies the consequences of the economic reforms for the previous social arrangements in the country, which were tied to individual work units-agriculture communes, collective firms, and state-owned enterprises. He continues with the social development during the reform period, reflecting a complex mix of social advances, mainly in terms of poverty reduction, and regresses for large population groups in terms of income security and human services, such as education and, in particular, health care. Next, the author discusses China's future policy options in the social field, whereby he draws heavily on relevant experiences in industrial countries over the years. The future options are classified into three broad categories: policies influencing the level and distribution of factor income, income transfers including social insurance, and the provision of human services.Economic Theory&Research,Banks&Banking Reform,Investment and Investment Climate,Privatization,Economic Systems
The design of a multicast-based distributed file system
No full textJetFile is a distributed file system designed to support shared file access in a heterogenous environment such as the Internet. It uses multicast communication and optimistic strategies for synchronization and distribution. JetFile relies on "peer-to-peer" communication over multicast channels. Most of the traditional file server responsibilities have been decentralized. In particular, the more heavyweight operations such as serving file data and attributes are, in our system, the responsibility of the clients. Some functions such as serializing file updates are still centralized in JetFile. Since serialization is a relatively lightweight operation in our system, serialization is expected to have only minor impact on scalability. We have implemented parts of the JetFile design and have measured its performance over a local-area network and an emulated wide-area network. Our measurements indicate that, using a standard benchmark, JetFile performance is comparable to that of local-disk b..
Spontaneous networking: an application-oriented approach to ad hoc networking
No full textAn ad hoc network must operate independently of a pre-established or centralised network management infrastructure, while still providing administrative services needed to support applications. Address allocation, name resolution, service location, authentication, and access control policies represent just some of the functionality that must be supported - without pre-configuration n or centralised services.
In order to solve these problems, it is necessary to leverage some aspect of the environment in which the network operates. We introduce the notion of a spontaneous network, created when a group of people come together for some collaborative activity. In this case, we can use the human interactions associated with the activity in order to establish a basic service and security infrastructure.
We structure our discussion around a practical real-world scenario illustrating the use of such a network, identifying the key challenges involved and some of the techniques that can be used to address them
The design of a multicast-based distributed file system [Elektronisk resurs]
No full textJetFile is a distributed file system designed to support shared file access in a heterogenous environment such as the Internet. It uses multicast communication and optimistic strategies for synchronization and distribution. JetFile relies on "peer-to-peer" communication over multicast channels. Most of the traditional file server responsibilities have been decentralized. In particular, the more heavyweight operations such as serving file data and attributes are, in our system, the responsibility of the clients. Some functions such as serializing file updates are still centralized in JetFile. Since serialization is a relatively lightweight operation in our system, serialization is expected to have only minor impact on scalability. We have implemented parts of the JetFile design and have measured its performance over a local-area network and an emulated wide-area network. Our measurements indicate that, using a standard benchmark, JetFile performance is comparable to that of local-disk based file systems. This means it is considerably faster than commonly used distributed file systems such as NFS and AFS.</p
The Design of a Multicast-based . . .
No full textJetFile is a distributed file system designed to support shared file access in a heterogenous environment such as the Internet. It uses multicast communication and optimistic strategies for synchronization and distribution. JetFile relie
