A distributed object-oriented system stresses moduality through narrow and rigidly defined interfaces to build low coupling, highly antonomous components. A security system for such systems must preserve the scalability, maintainability and extensibility of it. This paper presents a security system called Petrus, which provides strong authentication and data encyption to the Renaissance object environment. Petrus combines public-key and secret key cryptography to achieve acceptable performance. In addition, to minimize coupling, Petrus reduces functions of the central authorties and delegates authentication and data encryption to individual clients and servers. By hiding security functions in the Petrus Layers in proxies to remote objects, Petrus provides flexible mechanisms for applications that are mostly unaware of security to enforce constrains specified by their security policy, making it easy for the construction and maintenance of secure distributed systems.

An implemented system for on-line analysis of multiple distributed data streams is presented. The system is conceptually universal since it does not rely on any particular platform feature and uses format adaptors to translate data streams into its own standard format. The system is as powerful as possible (from a theoretical standpoint) but still efficient enough for on-line analysis thanks to its rule- based language (RUSSEL) which is specifically designed for efficient processing of sequential unstructured data streams. In this paper, the generic concepts are applied to security audit trail analysis. The resulting system provides powerful network security monitoring and sophisticated tools for intrusion/anomaly detection. The rule based and command languages are described as well as the distributed architecture and the implementation. Performance measurements are reported, showing the effectiveness of the approach.

After a brief survey of the problems related to audit trail analysis and of some approaches to deal with them, the paper outlines the project ASAX which aims at providing an advanced tool to support such analysis. One key feature of ASAX is its elegant architecture build on top of a universal analysis tool allowing any audit trail to be analysed after a straight format adaptation. Another key feature of the project ASAX is the language RUSSEL used to express queries on audit trails. RUSSEL is a rule-based language which is tailor-made for the analysis of sequential files in one and only one pass. The conception of RUSSEL makes a good compromise with respect to the needed efficiency on the one hand and to the suitable declarative look on the other hand. The language is illustrated by examples of rules for the detection of some representative classical security breaches.

This paper presents a framework for key escrow encryption that satisfies most law enforcement and civil liberties concerns. It provides users considerable autonomy in deciding how and with whom information will be escrowed. It relies on no specific technology solution but will accommodate all of them, whether implement- ed in hardware, software, firmware, or paper! Depending on the specific system, it may provide real-time emergency access to information when requested by authorized entities. Users, not governments, bear the costs of the scheme.

A system security engineering (SSE) methodology is used within the Secure Systems Engineering Department of AT&T Laboratories during the analysis, design, and integration of computer and network systems. This evolving methodology focuses on how threats, vulnerablilities, and attacks on these systems are identified and mitigated, and how safeguards based on engineering estimates of risk are identified and integrated.

This paper presents a simple tool to monitor and control incoming network traffic. The tool has been successfully used for shielding off systems and for detection of cracker activity. It has no impact on legal computer users, and does not require any change to exsisting system software or configuration files. The tool has been installed world-wide on numerous UNIX systems without any source code change.

The work that will be presented in this paper focuses on the use of Artificial Intelligence (AI) for certain computer security systems. We call this class of security systems “Intelligent Security Systems”. Some past works found AI helpful for such security systems as intrusion detection, virus detection, real time analysis of audit records, etc. But, because of the antagonism between security systems’ sensiblity and knowledge bases’ flexibility and friendliness, the use of AI in security cannot be effective without a real discussion between AI and security, namely, an interdisciplinary approach requiring two skills: Knowledge Engineering and security expertise.

In an age of expensive resources and technology, and the unique complexities brought about by the emerging markets, organizations share a common need and responsibility to manage those threats that impact on the operation of the business and profitablility. Inferably, when analysing threats to business in terms of a Risk Evaluation Framework, risk management and corporate security are similar in that each is concerned with the protection and conservation of corporate assets and resources. Whether it be proliferation of unfriendly acquisitions, domestic and international vulnerablility analysis and risk assessment, review of corporate security programmes and surveys, or disaster planning, disaster recovery, and continuity of operations, the need remains the same - security and managment of risks. While security has so often been an after thought, or rather a retrofit or ‘quickfix’, today’s insight of security involves sophistication, early product and business design, and a particular technical application never before realized. This article is an attempt to prove that today’s all encompassing corporate security process exsists as an essential element of the total risk management function.

* Users allowed to choose reusable passwords -> Weak passwords are often chosen. * A password is weak if it is 1. easy to guess, 2. simple to derive, or 3. likely to be found in a dictionary attack. * (attempted) solution: keep dictionary, try to look up newly chosen passwords. * Problem: the size of the dictionary makes storing it possibly searching it unattractive. *(New) solution: use a Bloom filter for reduced storage consumption and constant look-up time.

The Internet’s substantial growth has resulted in an increase in sophisticated security problems. The latest fad is network monitoring, or packet sniffing, whereby hackers collect account authorization data and use it to intrude on the Internet. To avoid this threat, users should get rid of any reusable, standard passwords and start utilizing one-time passwords only. Shadow passwords can also be used to avoid disclosing encrypted passwords. Security problems can also be avoided by verifying the proper system and service configurations. Systems managers should stay current with the latest software releases and bug fixes, utilize secure programming techniques and implement auditing programs to collect access data. Individual users should make an effort to understand and respect their site’s security policies, utilize available resources to protect their data, and follow Internet etiquette carefully. A list of resources for securing networks and systems is provided.

Cyberspace, the realm of computer networks voice mail and long-distance telephone calls, is increasingly important in our lives. Unfortunately, morally immature phreaks, cyberpunks and criminal hackers are spoiling it for everyone. Security professionals must speak out in the wider community and change the moral universe to include cyberspace.

The Internet is a vast sea of data represented in many formats and stored on many hosts. A large portion of the Internet is organized as the World Wide Web (WWW) which uses hypertext to make navigation easier than the traditional ways like anonymous FTP and Telnet. WWW browsers are used to navigate through the data found on the net.

Will the Internet replace private corporation data networks? Thanks to performance upgrades and new security schemes, it just might. The idea-once unthinkable because of the Net’s unpredictable performace and lack of security-has become viable thanks to the commercialization of the Internet backbone and the growing availability of sophisticated encryption authentication tools. Two or three years from now if a company is going to set up a wide-area-data- network, the Internet is going to be its first choice, says Pete Sinclair president and CEO of Smart Valley Inc., a Santa Clara, Calif., consortium formed to promote Internet-based electronic commerce in Silicon Valley.

The central role of audit trails, or (more properly) logs, in security monitor- ing needs little description, for it is too well known for any to doubt it. Auditing, or the analysis of logs, is a central part of security not only in computer system security but also in analyzing financial and other non-technical systems. As part of this process, it is often necessary to reconcile logs from different sources. Consider for example intrusion detection over a network. In this scenario, an intrusion detection system (IDS) monitors several host on a network, and from their logs it determines which actions are attempts to violate security (misuse detection) or which actions are not expected (anomaly detection). As some attacks involve the exploitation of concurrent commands, the log records may involve more than one user, process, and system. Further, should the system security officer decide to trace the connections back through other systems, he must be able to correlate the logs of the many different heterogenous systems through who the attacker may have come.

This has been another controversial year in the “growth” field of network and computer law. Recent cases will continue to fuel discussions inside and outside the Clinton Administration over protection of copyrighted information dist- ributed on computer networks. (NYT 7/7/94)