Concurrency control in trusted database management systems: a survey
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paper_title: Concurrency Control and Recovery in Database Systems

paper_content:

This book is an introduction to the design and implementation of concurrency control and recovery mechanisms for transaction management in centralized and distributed database systems. Concurrency control and recovery have become increasingly important as businesses rely more and more heavily on their on-line data processing activities. For high performance, the system must maximize concurrency by multiprogramming transactions. But this can lead to interference between queries and updates, which concurrency control mechanisms must avoid. In addition, a satisfactory recovery system is necessary to ensure that inevitable transaction and database system failures do not corrupt the database.
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paper_title: Nested Transactions An Approach To Reliable Distributed Computing

paper_content:

Thank you for reading nested transactions an approach to reliable distributed computing. Maybe you have knowledge that, people have search hundreds times for their chosen novels like this nested transactions an approach to reliable distributed computing, but end up in harmful downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they cope with some malicious virus inside their laptop.
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paper_title: Concurrency Control in Distributed Database Systems

paper_content:

Concurrency control is necessary and important in any multiusers, especially distributed database systems. In the paper we have briefly discussed the questions about concurrency control in distributed database systems, its eritieron of correctness, algorithms and techniques, and some questions related to its implementation such as deadloek, locks in relational database, robustness and so on.
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paper_title: Concurrency Control and Recovery in Database Systems

paper_content:

This book is an introduction to the design and implementation of concurrency control and recovery mechanisms for transaction management in centralized and distributed database systems. Concurrency control and recovery have become increasingly important as businesses rely more and more heavily on their on-line data processing activities. For high performance, the system must maximize concurrency by multiprogramming transactions. But this can lead to interference between queries and updates, which concurrency control mechanisms must avoid. In addition, a satisfactory recovery system is necessary to ensure that inevitable transaction and database system failures do not corrupt the database.
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paper_title: Federated database systems for managing distributed, heterogeneous, and autonomous databases

paper_content:

A federated database system (FDBS) is a collection of cooperating database systems that are autonomous and possibly heterogeneous. In this paper, we define a reference architecture for distributed database management systems from system and schema viewpoints and show how various FDBS architectures can be developed. We then define a methodology for developing one of the popular architectures of an FDBS. Finally, we discuss critical issues related to developing and operating an FDBS.
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paper_title: Database concurrency control in multilevel secure database management systems

paper_content:

Concurrent execution of transactions in database management systems (DBMSs) may lead to contention for access to data, which in a multilevel secure DBMS (MLS/DBMS) may lead to insecurity. Security issues involved in database concurrency control for MLS/DBMSs are examined, and it is shown how a scheduler can affect security. Data conflict security, (DC-security), a property that implies a system is free of covert channels due to contention for access to data, is introduced. A definition of DC-security based on noninterference is presented. Two properties that constitute a necessary condition for DC-security are introduced along with two simpler necessary conditions. A class of schedulers called output-state-equivalent is identified for which another criterion implies DC-security. The criterion considers separately the behavior of the scheduler in response to those inputs that cause rollback and those that do not. The security properties of several existing scheduling protocols are characterized. Many are found to be insecure. >
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paper_title: Multiversion concurrency control for multilevel secure database systems

paper_content:

Consideration is given to the application of multiversion schedulers in multilevel secure database management systems (MLS/DBMSs). Transactions are vital for MLS/DBMSs because they provide transparency to concurrency and failure. Concurrent execution of transactions may lead to contention among subjects for access to data, which in MLS/DBMSs may lead to security problems. Multiversion schedulers reduce the contention for access to data by maintaining multiple versions. A description is given of the relation between schedules produced in MLS/DBMSs and those which are multiversion serializable. The authors also propose a secure multiversion scheduler. They show that the scheduling protocol gives correct schedules and is free of covert channels due to contention for access to data, i.e. the scheduler is data-conflict-secure. >
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paper_title: Single-level multiversion schedulers for multilevel secure database systems

paper_content:

The concurrency control algorithms used for standard database systems can conflict with the security policies of multilevel secure database systems. The authors describe two new concurrency control algorithms that are compatible with common security policies. They are based on the multiversion timestamp ordering technique, and are implemented with single-level subjects. The use of only single-level subjects cannot introduce any additional threat of compromise of mandatory security; the analysis focuses on correctness. One of these algorithms has been implemented for Trusted ORACLE. >
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paper_title: Single-level multiversion schedulers for multilevel secure database systems

paper_content:

The concurrency control algorithms used for standard database systems can conflict with the security policies of multilevel secure database systems. The authors describe two new concurrency control algorithms that are compatible with common security policies. They are based on the multiversion timestamp ordering technique, and are implemented with single-level subjects. The use of only single-level subjects cannot introduce any additional threat of compromise of mandatory security; the analysis focuses on correctness. One of these algorithms has been implemented for Trusted ORACLE. >
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paper_title: Transaction Processing Using an Untrusted Scheduler in a Multilevel Database with Replicated Architecture

paper_content:

Abstract : Replicated architecture has been proposed as a way to obtain acceptable performance in a multilevel secure database system. This architecture contains a separate database for each security level such that each contains replicated data from lower security classes. The consistency of the values of replicated data items must be maintained without unnecessarily interfering with concurrency of database operations. This paper provides a protocol to do this that is secure, since it is free of covert channels, and also ensures one-copy serializability of executing transactions. The protocol can be implemented with untrusted processes for both concurrency and recovery.
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paper_title: A Single-Level Scheduler for the Replicated Architecture for Multilevel-Secure Databases

paper_content:

The replicated architecture for multilevel secure database systems provides security by replicating data into separate untrusted single-level database systems. To be successful, a system using the replicated architecture must have a concurrency and replica control algorithm that does not introduce any covert channels. Jajodia and Kogan (1990) have developed one such algorithm that uses update projections and a write-all replica control algorithm. The authors describe an alternative algorithm. The new algorithm uses replicated transactions and a set of queues organized according to security class. A new definition of correctness is required for this approach, so they present one and use it to show that the algorithm is correct. The existence of this new algorithm increases the viability of the replicated architecture as an alternative to kernelized approaches. >
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paper_title: A Practical Transaction Model and Untrusted Transaction Manager for a Multilevel-Secure Database System

paper_content:

Abstract : A new transaction model for multilevel-secure databases which use the replicated architecture is presented. A basic concurrency control algorithm and two variations are given based on this transaction model. We also present new correctness criteria for multilevel-secure databases which use the replicated architecture. Based on this criteria, we prove that our algorithms are correct.
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paper_title: Transaction Processing Using an Untrusted Scheduler in a Multilevel Database with Replicated Architecture

paper_content:

Abstract : Replicated architecture has been proposed as a way to obtain acceptable performance in a multilevel secure database system. This architecture contains a separate database for each security level such that each contains replicated data from lower security classes. The consistency of the values of replicated data items must be maintained without unnecessarily interfering with concurrency of database operations. This paper provides a protocol to do this that is secure, since it is free of covert channels, and also ensures one-copy serializability of executing transactions. The protocol can be implemented with untrusted processes for both concurrency and recovery.
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paper_title: A Single-Level Scheduler for the Replicated Architecture for Multilevel-Secure Databases

paper_content:

The replicated architecture for multilevel secure database systems provides security by replicating data into separate untrusted single-level database systems. To be successful, a system using the replicated architecture must have a concurrency and replica control algorithm that does not introduce any covert channels. Jajodia and Kogan (1990) have developed one such algorithm that uses update projections and a write-all replica control algorithm. The authors describe an alternative algorithm. The new algorithm uses replicated transactions and a set of queues organized according to security class. A new definition of correctness is required for this approach, so they present one and use it to show that the algorithm is correct. The existence of this new algorithm increases the viability of the replicated architecture as an alternative to kernelized approaches. >
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paper_title: A Multilevel Transaction Problem for Multilevel Secure Database Systems and its Solution for the Replicated Architecture

paper_content:

This paper sets out a second order modal logic for reasoning about multilevel security in probabilistic systems. We present a possible world semantics and prove that the logic is sound with respect to it. The semantics is novel in treating probability measures themselves as possible worlds. We give a syntactic definition of security and show that the semantic interpretation of our syntactic definition is equivalent to an earlier independently motivated characterization, Probabilistic Noninterference ([141). We also look at a syntactic representation of Grays Applied Flow Model (a special case of McLean's Flow Model, given in [25]), and discuss the relation between these characterizations of security andbetween their usefulness in security analysis. We give a syntactic description of a round-robin server and sketch the formal proof of its security.
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paper_title: Synchronization with eventcounts and sequencers

paper_content:

Synchronization of concurrent processes requires controlling the relative ordering of events in the processes. A new synchronization mechanism is proposed, using abstract objects called eventcounts and sequencers, that allows processes to control the ordering of events directly, rather than using mutual exclusion to protect manipulations of shared variables that control ordering of events. Direct control of ordering seems to simplify correctness arguments and also simplifies implementation in distributed systems. The mechanism is defined formally, and then several examples of its use are given. The relationship of the mechanism to protection mechanisms in the system is explained; in particular, eventcounts are shown to be applicable to situations where confinement of information matters. An implementation of eventcounts and sequencers in a system with shared memory is described.
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paper_title: Orange Locking: Channel-Free Database Concurrency Control Via Locking

paper_content:

Abstract : The concurrency control lock (e.g. file lock, table lock) has long been used as a canonical example of a covert channel in a database system. Locking is a fundamental concurrency control technique used in many kinds of computer systems besides database systems. Locking is generally considered to be interfering and hence unsuitable for multilevel systems. In this paper we show how such locks can be used for concurrency control, without introducing covert channels.
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paper_title: Alternative correctness criteria for concurrent execution of transactions in multilevel secure databases

paper_content:

Investigates issues related to transaction concurrency control in multilevel secure databases. This paper demonstrates how the conflicts between the correctness requirements and the secrecy requirements can be reconciled by proposing two different solutions. It first explores the correctness criteria that are weaker than one-copy serializability. Each of these weaker criteria, though not as strict as one-copy serializability, is required to preserve database consistency in some meaningful way, and moreover, its implementation does not require the scheduler to be trusted. It proposes three different, increasingly stricter notions of serializability (level-wise serializability, one-item read serializability and pair-wise serializability) that can serve as substitutes for one-copy serializability. The paper then investigates secure concurrency control protocols that generate one-copy serializable histories and presents a multiversion timestamping protocol that has several very desirable properties: it is secure, produces multiversion histories that are equivalent to serial one-copy histories in which transactions are placed in a timestamp order, eliminates starvation and can be implemented using single-level untrusted schedulers.
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paper_title: A two snapshot algorithm for concurrency control in multi-level secure databases

paper_content:

A concurrency control algorithm for replicated, secure, multilevel databases is presented. Multiversion and replicated databases can avoid starvation problems without introducing indirect channels by maintaining stable copies of old low-level data values for use by high-level transactions. The algorithm presented improves on two comparable techniques, a direct multiversion approach of T. F. Keefe and W. T. Tsai and the full replication scheme of S. Jajodia and B. Kogan (both in Proc. 1990 IEEE Symp. on Res. In Security & Privacy, May 1990). In the latter, each security level has a container that holds a copy of all lower-level data. It is shown that only a constant number of old copies (two, as it turns out) must be maintained. The correctness of the algorithm is argued, and it is demonstrated that the algorithm is free of indirect channels and starvation. >
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Title: Concurrency Control in Trusted Database Management Systems: A Survey

Section 1: INTRODUCTION
Description 1: Provide an overview of the paper, motivations for studying concurrency control in trusted DBMS (TDBMS), and the organization of the survey.

Section 2: A BRIEF OVERVIEW CONCURRENCY CONTROL IN DBMSs
Description 2: Discuss current trends and historical developments in concurrency control methodologies in traditional database management systems.

Section 3: CONCURRENCY CONTROL ALGORITHMS IN TRUSTED DATABASE MANAGEMENT SYSTEMS
Description 3: Detail the various concurrency control algorithms specifically developed for TDBMS, classify them, and discuss their mechanisms.

Section 4: MULTIVERSION ALGORITHMS
Description 4: Explain the multiversion scheduling algorithms and how they handle security and consistency in a TDBMS.

Section 5: REPLICATED ARCHITECTURE
Description 5: Describe the concurrency control algorithms for TDBMS environments that use a replicated architecture.

Section 6: DISTRIBUTED DATABASE MANAGEMENT SYSTEMS
Description 6: Provide an overview of concurrency control algorithms tailored for trusted distributed database management systems.

Section 7: OBJECT-ORIENTED DATABASE MANAGEMENT SYSTEMS
Description 7: Examine the concurrency control approaches for secure object-oriented database management systems.

Section 8: OTHER ALGORITHMS
Description 8: Discuss other notable algorithms related to securing and ensuring consistency in multilevel and trusted DBMSs.

Section 9: DIRECTIONS FOR FURTHER RESEARCH
Description 9: Outline potential areas for future research and development in the field of concurrency control for trusted database management systems.