Physical & Network Fault Tolerance - Essay Example

Running head: Physical & Network Fault Tolerance Physical & Network Fault Tolerance Introduction Fault tolerance is the ability of a system in response to an unexpected hardware or software failure. Most of the current systems have the backup facilities which help the users to restore their important data even if the system crashes. The external and internal parameters of the system often cause problems to the system. The internal parameters of the system needs stabilized external environment in order to function properly.Fault tolerance is a general term associated with physical things, networks, databases, software, system etc. This paper analyses the technologies and alternatives associated with Physical & Network fault tolerance. Technologies and alternatives associated with Physical & Network Fault Tolerance Advanced planning and a proactive anticipation are necessary to avoid the problems caused by fault tolerance. It is better to incorporate the preventive measures while constructing the system itself rather than searching for solutions at a later stage when the problem occurs. The solution for a system failure can be addressed mainly in two ways; Design systems that are more reliable or fail less often; Design systems with built-in redundancy so that critical systems have backups that will continue to function should primary systems fail. (Fault Tolerance Reading Material, p.2) The first option seems to be bit difficult since apart from the internal parameters, external parameters also can cause system failures. The external parameters are always changing and it is probably impossible to make a system which can work every where under any circumstances. For example, some countries use 220V power supply whereas some others use 110V power supply. Moreover in some countries, the heat and humidity might be so high whereas in some other countries or locations it might be the opposite case. So constructing a system which can withstand any kind of external threat might be difficult. On the other hand, systems with facilities like backups even if the primary system fails, might be a good idea in tackling the system faults. Power is one of the prominent entities associated with physical fault tolerance. External power loss often creates problems to physical systems. Most of the physical systems are using IC chips which operate on a low power and require stabilized power supplies for the safe functioning. The sudden breakage of power will often damage these volatile equipments and the system. So, the systems need uninterrupted power supplies (UPS) and attaching a UPS to the system often minimizes the problems due to unexpected power failures or voltage variations. Heat and humidity are other physical factors which can affect the functioning of a system. Electronic components are always volatile to weather conditions. All the modern systems use electronic components and for the safe functioning of these components safe temperature and humidity conditions must be administered in the rooms where these systems were installed. In order to maintain stabilized climate, air conditioners must be used in the rooms where the systems were installed. Network fault tolerance is another area of concern while using systems in conjunction. Networks must be designed in such a way that even if one computer create some problems in accessing the network, other computers should function normally. If the network administrators adopt point to point or star designs for the networking process, a single point failure can cause problems to all the computers in the network. “Point to point, hierarchical and star designs are far more subject to single points of failure than ring designs. Rings offer multiple paths of data across a network between users and the computers they use. In hierarchical, star or linear bus designs, a single break in a physical wire or the failure of a network hardware can result in the isolation of large sets of users from the resources that they need to communicate with” (Fault Tolerance Reading Material, p.4) Overload, power failure, viruses, computer failure, data loss, etc are some of the other major reasons for the network failures. (Fault tolerance) Before taking precautions for avoiding unexpected system failures the following points must be considered. First, identify scenarios and situations that may cause system loss or failure. Next, assess likelihood of each occurrence. Then, assess duration of each failure. Assess severity of the associated loss. Assess cost of these failures. Assess feasibility of a fault tolerance solution. Assess cost of the solution. (Fault Tolerance Reading Material, p.11) Every precautionary measures must be equated against the expense and utility associated with it before taking decisions about implementing it. For example, big organizations often may have lot of computers which were networked and often need expensive methods to counter the problems caused by system faults due to internal and external parameters. On the other hand a home user of computer does not require such expensive activities to protect their computer from crashing. The main advantage of fault tolerant systems is the safety of the data stored in such systems. Modern world has almost completely removed the paper works or filing of the documents from their personal or professional life and electronic data are used to conserve important things on computer systems. The safety of this electronic data is important and for that purpose fault tolerant systems can help us up to certain extent. But the main disadvantage of fault tolerant servers is their inability to safeguard a wide range of systems.”Fault tolerant servers provide CPU and component redundancy within a single enclosure, but they cannot protect against larger-scale outages such as campus wide power failures, campus wide connectivity issues, and loss of network or storage connectivity” (Protecting Mission-Critical Workloads with VMware Fault Tolerance, p.3) Conclusions Physical and network problems are common to computer related systems in the modern era due to various internal and external parameters. The internal components of these systems need constant external parameters like stabilized electricity, controlled heat and humidity. The cost and benefit of taking precautionary measures to avoid problems depend on the purpose for which the system is used. For professional users, the system needs high level of protection whereas for home users the protection need not be of highest standards. References 1. Fault Tolerance Reading Material,2005, College of Information Systems and Technology, University of Phoenix, 2. Fault tolerance, Retrieved on 10 September 2009 from http://www.computerhope.com/jargon/f/faulttol.htm 3. Protecting Mission-Critical Workloads with VMware Fault Tolerance, Retrieved on 10 September 2009 from http://74.125.153.132/search?q=cache:vSVizk_tYVcJ:www.vmware.com/files/pdf/resources/ft_virtualization_wp.pdf+Key+vendors+and+approximate+costs+of+Fault+Tolerance&cd=1&hl=en&ct=clnk Read More