1.1 Introduction
Fault-tolerance is the process of working of a system in a proper way in spite of the occurrence of the failures in the system. Even after performing the so many testing processes there is possibility of failure in system. Practically a system can’t be made entirely error free. Fault-tolerant computing already plays a major role in process control, transportation, electronic commerce, space, communications and many other areas that impact our lives. Many of its next advances will occur when applied to new state-of-the-art systems such as massively parallel scalable computing, promising new unconventional architectures such as processor-in-memory or reconfigurable computing, mobile computing, and the other exciting new things that lie around the corner.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Research hypothesis and questions, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In the past twenty years, fault-tolerant computing has led into a broad discipline encompassing many aspects of computer design. This article is intended to provide the reader with an overview of the different thrust areas which encompass hardware and software fault tolerance. During the 1970s, two influential fault-tolerant machines were developed by NASA for fuel-efficient aircraft that require continuous computer control in flight. They were designed to meet the most stringent reliability requirements of any computer to that time. Both machines employed hybrid redundancy.
The first, designated Software Implemented Fault Tolerance (SIFT), was developed by SRI International. It used off-the-shelf computers and achieved voting and reconfiguration primarily through software. The second machine, the Fault-Tolerant Multiprocessor (FTMP), developed by the C. S. Draper Laboratory, used specialized hardware to affect error and fault recovery. A commercial company, August Systems, was a spin-off from the SIFT program. It has developed a TMR system intended for process control applications.
Fault tolerance and dependable systems research covers a wide spectrum of applications ranging across embedded real-time systems, commercial transaction systems, transportation systems, and military/space systems to name a few. The supporting research includes system architecture, design techniques, coding theory, testing, validation, proof of correctness, modeling, software reliability, operating systems, parallel processing, and real-time processing. These areas often involve widely diverse core expertise ranging from formal logic, mathematics of stochastic modeling, graph theory, hardware design and software engineering.
Fault-tolerance is achieved by applying a set of analysis and design techniques to create systems with dramatically improved dependability. As new technologies are developed and new applications arise, new fault-tolerance approaches are also needed. In the early days of fault-tolerant computing, it was possible to craft specific hardware and software solutions from the ground up, but now chips contain complex, highly-integrated functions, and hardware and software must be crafted to meet a variety of standards to be economically viable. Thus a great deal of current research focuses on implementing fault- tolerance using COTS (Commercial-Off-The-Shelf) technology.
Recent developments include the adaptation of existing fault-tolerance techniques to RAID disks where information is striped across several disks to improve bandwidth and a redundant disk is used to hold encoded information so that data can be reconstructed if a disk fails. Another area is the use of application-based fault-tolerance techniques to detect errors in high performance parallel processors. Fault-tolerance techniques are expected to become increasingly important in deep sub-micron VLSI devices to combat increasing noise problems and improve yield by tolerating defects that are likely to occur on very large, complex chips.
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to know the Fault Tolerance in a Computer System.
1.3 Statement of Problems
Investigation revealed that the use of application-based fault-tolerance techniques to detect errors in high performance parallel processors. Fault-tolerance techniques are expected to become increasingly important in deep sub-micron VLSI devices to combat increasing noise problems and improve yield by tolerating defects that are likely to occur on very large, complex chips.
1.4 Aim and Objectives of Study
The aim of the study is to examine the Fault Tolerance in a Computer. In achieving this aim, the following specific objectives were laid out as follows:
- To identify the faults in computer system.
- To investigate the causes of computer system faults.
- To proffer solution to the detected faults in a computer system.
1.5 Research Questions
The study came up with research questions so as to be able to ascertain the above stated objectives. The specific research questions for the study are stated below as follows:
- Are there solutions to computer system hardware and software faults?
- What are the faults of computer system?
- What the causes of computer system faults?
1.6 Significance of Study
This study will be of immense benefit to computer engineers and other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.7 Scope of Study
The scope of the research is focused on detection of Fault Tolerance in a Computer System.
1.8 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).