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ACID (Atomicity, Consistency, Isolation, and Durability) is a set of properties that guarantee the reliability of database transactions [2]. ACID properties were initially developed with traditional, business-oriented applications (e.g., banking) in mind. Hence, they do not fully support the functional and performance requirements of advanced database applications such as computer-aided design, computer-aided manufacturing, office automation, network management, multidatabases, and mobile databases. For instance, transactions in computer-aided design applications are generally of long duration and preserving the traditional ACID properties in such transactions would require locking resources for long periods of time. This has lead to the generalization of ACID properties as Recovery, Consistency, Visibility and Permanence. The aim of such generalization is to relax some of the constraints and restrictions imposed by the ACID properties. For example, visibility relaxes the isolation property by enabling the sharing of partial results and hence promoting cooperation among concurrent transactions. Hence, the more generalized are ACID properties, the more flexible is the corresponding transaction model.

Modern production management systems consist of transaction processing systems and decision enhancement systems. A clear example of two such components are an ERP systems and APS systems. These systems are often standard software systems, and therefore suitable for many different situations. This paper analyses the combination of ERP and APS from the perspective of change. The paper builds on a classification of ERP-APS integrations and an analysis of changeability of ERP systems. The paper elaborates on issues encountered when changing ERP-APS integrations. The main conclusion is that such changes are technically complex because of different technologies and different data models used. Therefore, end user education and training is emphasized Moreover, they are organizationally complex because many stakeholders are involved.

Transaction level modeling (TLM) aims at abstract description and highperformance simulation of bus-based System-on-Chip (SoC) platforms. While languages and libraries providing the necessary basic modeling mechanisms are available, there is ongoing discussion on modeling styles for their usage. This contribution employs object-oriented modeling of transaction data and bus protocols, targeting at better extensibility and reuse of models. Our simulation performance measurements show that by abstracting from signal-level data representations, a cycle-accurate object-oriented model can achieve performance close to models on cycle-approximate level.

This paper seeks to develop a conceptual model that is inherently suitable for analyzing the complexity of B2B e-market and transaction performance in China. The case study of CCEC.com provides an insight on how one excellent B2B e-market has executed a successful strategy utilizing the existing source within the current business climate of China. The data from the case research illustrate e-commerce strategies and crucial business activities. Further, the B2B E-Market Model is proposed for studying the critical strategy component of value creation in e-markets of China. The Model involves with two variables: the e-commerce process and the controlling complexity. Building on process insight, the e-commerce process can be modelled by separating main business activities into four phases designed to exploit value creation opportunity. Controlling complexity refers to supervising and controlling the transactional processes for security, trust and efficient transaction environment. The Model illustrates the relationship between the business components required to support the e-commerce processes with the value creation factor and the controlling complexity. Using the model in comparisons of B2B e-markets in USA and in China, we find unique characteristics in transactional processes - the information, negotiation, payment and delivery phases. It offers an effective approach to studying dynamic structure of transactional process and a high performance e-commerce strategy.

A real-time database system supports a mix of transactions. These include the real-time transactions that require completion by a given deadline. The present study makes an effort to introduce a higher level of parallelism for execution of real-time transactions. It considers extensions within a transaction processing system. These permit a real-time transaction to avoid delays due to ordinary transactions. In effect, it is a model of transaction execution that permits execution of real-time transactions without interference from other executing transactions, and by reducing other probabilistic delays associated the with competing real-time transactions.

The 1960s saw the emergence of Electronic Data Processing or EDP systems. EDP systems are still available today and are simply ‘automation engines.’ That is EDP systems are used to automate routine operations of an organisation, focussing on accounting and transaction processing. For our purposes EDP systems are synonymous with On-Line Transaction Processing (OLTP) systems. We note, however, that the success of EDP/OLTP systems lead to an evolution in the use computerised systems, in contributing to the orderly and efficient running of the organisation. Since then the hardware and software technologies have gone through many generations of evolution. File management systems, database systems, relational databases, and on-line analytical processing represent different points in this historical sequence. They encapsulate the technologies used in storing and manipulating data and information in progressively better ways and in greater volumes. Today the use of information systems (IS), or in more common parlance, information technology (IT), in a management context, is the leading issues for the organisation. We focus mainly on IS which —in one way or another- were thought to make a valuable contribution to decision support, and certainly with IS in an organisational context.

Early computer applications spawned structured applications. Structured applications led to online applications. Online applications processed business transactions and became essential to the day to day running of the corporation. As these transaction processing applications aged, they became legacy applications. Corporations thought they had a foundation for information with their transaction processing applications, but they were wrong. The many transaction processing applications were unintegrated, did not store historical data to any great extent, and stored data in technology difficult to access. The result was a great thirst for information. The thirst for information from legacy applications fostered the data warehouse environment. The data warehouse environment focussed on granular, integrated, historical data that was easy to access and was able to be reshaped in as many ways as the corporation needed to see the data. From the foundation of the data warehouse evolved the corporate information factory, where there are many different components each of which serves a different community and purpose.

Multilevel secure transaction processing has been well explored in the past decade. Despite this research, the proposed secure concurrency control protocols are not completely satisfactory because of the stringent constraints imposed by multilevel security. In this paper, we argue that modeling a transaction as an extended transaction model could significantly reduce the performance penalty. We accomplish this by minimizing (1) the probability of restarting a high security level transaction; and (2) the portion of the transaction to be reexecuted, when a restart becomes inevitable. In particular, we exploit the non-flat nature of transactions by identifying dependencies among various components of a transaction and portraying a transaction as an advanced transaction model. We demonstrate, via formal proofs, that our approach preserves the semantics of the transaction, and our concurrency control algorithm guarantees serializability.

The mobile computing paradigm has emerged due to advances in wireless or cellular networking technology. This rapidly expanding technology poses many challenging research problems in the area of mobile database systems. Mobile users can access information independent of their physical location through wireless connections. However, accessing and manipulating information without restricting users to specific locations complicates data processing activities. There are computing constraints that make mobile database processing different from the wired distributed database computing. In this chapter, we survey the fundamental research challenges particular to mobile database computing, review some of the proposed solutions and identify some of the upcoming research challenges. We discuss interesting research areas, which include mobile location data management, transaction processing and broadcast, cache management and replication. We highlight new upcoming research directions in mobile digital library, mobile data warehousing, mobile workflow and mobile web and e-commerce.

In this paper, we define a language for specifying security protocols concisely and unambiguously. We use this language to formally specify the protocol for payment transactions in Secure Electronic Transaction (SET), which has been developed by Visa and MasterCard.

In this chapter, we discuss how the transaction processing solutions presented earlier can be applied in both hierarchical and replicated databases. In each case, we begin with a brief introduction and a description showing how hierarchical and replicated databases are structurally similar to MLS databases.

A system that is specifically designed for efficiently processing transactions with timing constraints is referred to as aReal-Time Database System(RTDBS). The objective of the system here is to meet the transaction deadlines, that is, to process transactions before their deadline expires. RTDBS’s performance is often measured in terms of miss percentage or the fraction of transactions that are unable to complete before their deadline expires. Typically, an RTDBS should keep the miss percentage as low as possible. In addition to improving real-time performance by helping the transactions to meet their individual time constraints, an RTDBS has to ensure the data integrity constraints just like in a conventional transaction processing scenario. In other words, RTDBS design becomes significantly complex due to having to address the above two constraints simultaneously. Over the past decade, a considerable amount of research has been devoted for developing priority assignment mechanisms, concurrency control techniques, buffer management policies, and transaction processing components that are specifically tailored for the RTDBS environment. However, the issue of ensuring security of RTDBS began to receive adequate research attention only recently.

In this chapter, we review the research efforts towards developing secure transaction processing algorithms. A secure transaction processing protocol, in addition to complying with the two Bell-LaPadula restrictions, must be free of all covert channels. This requirements prohibits the use of conventional concurrency control and commit protocols since they are susceptible to covert channels.

The focus of our previous chapters was on concurrency control related issues arise in MLS DBS environment. In this chapter, we shift our attention to another important transaction processing component, namely, buffer management. Since transactions of various security clearance levels often share the buffer pool, there arise the possibility of exploiting some of the buffer management components for covert signaling. In order to ensure the security of MLS RTDBS, buffer managers should be designed to meet the non-interference [GM82] criteria.

The primary purpose of a database management system is to carry out transactions. A transaction is a sequence of database operations either to query or manipulate data in a shared database. The goal of a concurrency control (CC) mechanism is to preserve database integrity, even in the presence of concurrent data accesses by multiple users, by properly synchronizing simultaneous executions of transactions. This goal is best illustrated by a simple example.

We propose and evaluate a simplified technique for studying the architectural behavior of database workloads. This “microbenchmark” technique poses simple queries of the database to generate the same dominant I/O patterns exhibited in more complex, fully-scaled workloads. The potential benefits from this microbenchmark approach include smaller hardware requirements, less extensive workload parameter tuning, and simpler database parameter tuning. We demonstrate that the microbenchmark workload exhibits processor and memory system behavior relatively similar to that of the more complex standardized benchmarks. We also enumerate several factors that impact the representativeness of these microbenchmark workloads.

In this paper we describe how a set of autonomous computational agents can cooperate in providing coherent management of information in environments where there are many diverse information resources. The agents use models of themselves and of the resources that are local to them. Resource models may be the schemas of databases, frame systems of knowledge bases, or process models of business operations. Models enable the agents and resources to use the appropriate semantics when they inter-operate. This is accomplished by specifying the semantics in terms of a common ontology. We discuss the contents of the models, where they come from, and how the agents acquire them. We then describe a set of agents for telecommunication service provisioning and show how the agents use such models to co-operate. Their interactions produce an implementation of relaxed transaction processing.