From the Publisher:
The book studies modern concepts of Computer Security. It is selfcontained in the sense that it introduces the basic mathematical background necessary to follow computer security concepts. Next we examine modern developments in Cryptography starting from private-key and public-key encryption, going through hashing, digital signatures, authentication, secret sharing, group-oriented cryptography, pseudorandomness, key establishment protocols, zero-knowledge protocols, identification and finishing with an introduction to modern e-business systems based on digital cash. Intrusion detection and access control provide examples of security systems implemented as a part of operating system. Database and network security is also discussed.

Fundamentals of Computer Security

The personal model of data

Systems and methods are provided for the detection and prevention of intrusions in data at rest systems such as file systems and web servers Item requests are examined to determine if the request and/or the result violates an item access rule If either the request or the result violates the item access rule, an access control manager is alerted and appropriate action is taken such as not complying with the item request Embodiments of the invention also produce a scorecard to represent the severity of an intrusion threat

Data security and intrusion detection

Systems and methods are provided for data protection across connected, disconnected, attended, and unattended environments. Embodiments of the inventions may include differential encryption based on network connectivity, attended/unattended status, or a combination thereof. Additional embodiments of the invention incorporate “trust windows” that provide granular and flexible data access as function of the parameters under which sensitive data is accessed. Further embodiments refine the trust windows concept by incorporating dynamic intrusion detection techniques.

Differential encryption utilizing trust modes

A method and an apparatus for processing data provides protection for the data. The data is stored as encrypted data element values (DV) in records (P) in a first database (0-DB), each data element value being linked to a corresponding data element type (DT). In a second database (IAM-DB), a data element protection catalogue (DC) is stored, which for each individual data element type (DT) contains one or more protection attributes stating processing rules for data element values (DV), which in the first database (0-DB) are linked to the individual data element type (DT). In each user-initiated measure which aims at processing a given data element value (DV) in the first database (0-DB), a calling is initially sent to the data element protection catalogue for collecting the protection attribute/attributes associated with the corresponding data element types. The user's processing of the given data element value is controlled in conformity with the collected protection attribute/attributes.

Data security system for a database

Data protection in computer systems is a rather complex problem. Data has to be protected while it is in memory, during communication and while it is stored on mass storage devices. During computation the central processor executes instructions and operates on data that are in readable form. The problem of operating on encrypted data was first considered by Rivest et al [4]. However, notrivial privacy homomorphisms do not exist. Thus it seems that isolation of users is the only alternative if security and privacy is to be achieved. However, in practice isolation is difficult to enforce. Worse, when user to user communication is allowed, more serious loopholes develop. Even though the problems of protection in Operating Systems in general are difficult, one does not have to settle for no security. Encryption allows the protection of data even when good security measures are lacking in an Operating System. In fact it is possible to design operating systems with improved protection using encryption [3]. In this paper we shall consider the problems of encrypted relational datsbases and show that it is possible under some circumstances to perform relational operations without decrypting an entire record.

Y. Yeh

Papers

Cryptographic Relational Algebra