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The purpose of a new system can also be to increase productivity or quality of the output or to minimize costs. Computer system includes the hardware, software, and people working within it or using it in the immediate environment. Planning a new system is the process of thinking about various details and organizing the activities required to achieve the desired goal. <— System analysts do this job Current System: investigation, collection of data, analysis Evaluation of current system: What works good, and what doesn’t? Propose new system Factors to consider: Compatibility to old system Infrastructure Hardware/Software requirements Cost Time Staffing Ethical issues Change management is necessary in order to facilitate the shifting of individuals, teams, hardware, software in order to ensure that changes are implemented fully. The need for change management is because change is risky , and change management allows for handling change with the least disruption to the organization DESCRIBE THE NEED FOR CHANGE MANAGEMENT Planning transition to the new system Hardware Communications equipment and software System software Documentation and support Running and maintaining system Approval by management Type of implementation of the new system Implemented with minimal and accepted risk to existing infrastructure Improved functionality and stability The term legacy system refers to old technology. These systems may be still in use but are definitely in need of replacement. Business Mergers are the legal consolidation of two entities into one entity. Issues like language differences and different software, conventions, and currencies are always problems. Legacy Systems: Old systems, often inherited from another company
Outdated Poor competitiveness & compatibility to modern equivalents Evaluation of system replacement costs vs. maintaining costs Business mergers: Time and money in replacing the system vs. Data redundancy running systems independently Language differences Different versions of a system in an international business may create issues American vs European system (metric vs. Imperial) Data structures Different system environments Software as a Service (SaaS): ADVANTAGES: -No/Low cost in employing personnel to maintain system -Software manufacturer can provide help in cases of malfunction -Maintenance and updating management by soft. manufacturer -Client enjoys the professional know-how of the software manufacturer DISADVANTAGES: -Data security issues resulting from trusting your info with someone else (loss of control) -Downtime (loss of connectivity means you can’t use system) -Compliance (when data resides in a service provider’s data center, ensuring that an organization complies with the relevant gov’t data - protection regulations) Software-as-a-service: Remotely hosted computer system Servers lend from software manufacturer Managed and maintained by software manufacturer Application Service Provider (ASP) Computer the word is a derivative of the word “computes” , which has Latin and French origins ( computāre and putāre ) meaning to think, estimate, count, and figure. it is a device we have created to assist with this (usually electronic in nature), so it could be defined as a built device that thinks and count. The word “system” also comes from the Latin “systema” which means an organized whole composed of parts So we are talking about an organized collection of built parts that help us to think and count. Computing devices - it brings up images of a variety of devices including desktop computers, laptops, tablets, smart phones, etc. as well as all the Peripheral devices. Peripheral devices - devices that add on to the Main Computing device. System Analyst - someone who specializes in analyzing, designing, and implementing computer systems. They are familiar with the types of systems and analyzes what would be best for the users within a particular system The term “system analyst” is also an umbrella term that includes:
-All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria We need to design a new system or modify an existing system , so we need to analyse what’s going on first – this can be done a number of ways including: Observation is the process of monitoring a system while it is at work (ex: An awkward man stands behind a store clerk for one whole day, seeing how she works) Pros : as it is not based on numerical statistics, it can explore topics in great detail and depth, and uninstructive observation will create extremely natural data Cons : a functioning system that is being observed will always act different than it does normally, and the non statistical data can be difficult to analyze and can cause generalizations. Focus Groups is a form of research in which a group of people, generally stakeholders, are gathered together and questioned on their opinions towards a project or product (questions are generally asked in an interactive group setting where the participants are free to talk with other members in the group) Pros : are the researcher can interact with the participants, pose follow-up questions or ask questions that probe more deeply, and results can be easier to understand than complicated statistical data, and the researcher can get information from non-verbal responses, such as facial expressions or body language(information is provided more quickly than if people were interviewed separately) Cons : Respondents may not feel encouraged to provide accurate or honest answers, and may not be fully aware of their reasons for any given answer because of lack of memory on the subject, or even boredom – also the number of respondents who choose to respond to a survey question may be different from those who chose not to respond, thus creating biased data Interview is a face to face meeting, that consists of an interviewer asking the interviewee questions that should be pertinent to the topic of the interview Pros : you get direct feedback from stakeholders, you can ask any question you want, and can change the direction of the interview, people tend to be more truthful face to face, you can see how people physically react to certain questions, and you can discuss a topic in depth Cons : it takes a long time to interview everyone, it is quite costly as people have to stop working to go to the interview and you have to pay the interviewers. Once we have some initial information about the system from our observations, focus groups , and interviews of the stakeholders – now we can look deeper into the system: We can understand the workflow of the system What are the entry points (inputs) and exit points(outputs) of the system What are the competitors (e.g. competing software) and could we learn from them What suggestions from within the system to improve could we incorporate (from the stakeholders) The first change is sometimes called a prototype The prototype is essentially a change to the system designed to be tested by the users of the system to make sure it: Meets the requirements of the system Matches the capabilities of the previous system Improves on the capabilities of the previous system Measuring if this is accomplished is by once again involving the stakeholders and “testing” if these criteria are being met or if there is a “bug” in the prototype to report (essentially a “bug” would mean one of those criteria is not being met in some way)
Then we would return to redesign the prototype and test again. This process is often called a design cycle, iterative system , or a feedback loop The process of prototyping has been used in software development (in some form) since the 1970s and can sometimes use terminology like “alpha phase” and “beta testing” as it applies to prototyping The basic process of prototyping involves the following steps:
- Identify basic requirements – including the input and output information desired, but details, such as security, can typically be ignored
- Develop Initial Prototype – that includes only user interfaces
- Review – where the customers, including end-users, examine the prototype and provide feedback on additions or changes
- Revise and Enhance – using the feedback both the specifications and the prototype can be improved An iterative system helps you find problems quickly because it makes it easy to try it again Problems can be quickly fixed through an iteration which should be tested to make sure the "fixes" went through and solved, and it also finds any new usability problems by the new changed design Iterative design is specifically aimed to teach you through messing up repetitively until you get it right resulting in a more successful final product, and when applied early in the development stage, significant cost savings are possible. Different companies use different variations on a feedback loop, iteration. Once the prototype is in place, the system starts testing and providing feedback on the system Failing to include the end user in the process can lead to several problems including: The end product not meeting their requirements Being inappropriate from the intended use The system might have a bias towards the developers and not all users This feedback with developers, users, the hardware, the software, etc. within a system can sometimes be summarized as “Information Technology” (or “IT” ) Information technology (IT) can be defined as: “The use of any computers, storage, networking and other physical devices, infrastructure and processes to create, process, store, secure and exchange all forms of electronic data” One such concern could be the rate at which technology is being introduced and issues that may arise from insufficient testing in critical situations (such as air traffic control) The ultimate fear of many people is that future systems will be programmed to make decisions that would be better taken by humans , such as the decision to deploy nuclear weapons (i.e. Skynet and the terminators) There are also social impacts such as internet addiction , where people feel that they can never get away from IT and are trapped on a “digital treadmill” These ethical concerns leads to the term “digital citizenship” – which can be defined as appropriate behavior that represents the responsible, ethical and legal approach that individuals take in any situation with respect to the use of IT. Digital citizenship permeates, in one way or another, all of the preceding social and ethical considerations, and these may be related to changes in attitudes towards the use of IT systems, or new developments in IT such as social networking or cyber bullying.
Change is always hard for a system, so managing this change it important – leading to the term “change management” Change Managemen t refers to any approach to transitioning individuals, teams, and organizations using methods intended to re-direct the use of resources, business process, budget allocations, or other modes of operation that significantly reshape a company or organization Change Management will benefit the aims of the company and monitor assumptions, risks, dependencies, costs, return on investment, dis-benefits and cultural issues affecting the aim of the company Change Management involves : Explaining why change is taking place, the benefits of successful change (what is in it for us, and you) as well as the details of the change (when? where? who is involved? how much will it cost? etc.) Devise an effective education , training system Counter resistance from the employees of companies and persuade them to change Provide personal counseling (if required) to alleviate any change-related fears Monitor the change and address any updates The need for change management is based on the need to make sure that new systems work with the old systems Often the term is “legacy system” Legacy system is an old method, technology, computer system, or application program, "of, relating to, or being a previous or outdated computer system" implying that the legacy system is out of date or in need of replacement Disadvantages : The cost of maintaining an older system can be higher than maintaining a more updated version The staff might not be familiar with such an outdated version of the system Tech support may no longer be available The data in the current system might not be compatible with newer systems and conversion may not be possible Legacy systems are usually more vulnerable to security threats due to lack of security patches In the change over, this might be a complicated process as you might be moving from: Different hardware to a different technology (e.g. desktops to laptops, laptops to tablets, iPhones to Android phones, etc.) Different OS (e.g. Apple to Windows, Linux, Unix, etc.) Different software (e.g. Microsoft Office to Google Docs, etc.) Different file system (e.g. server file storage to cloud storage) Or even a combination of change factors to manage One more modern solution is to move to “Software as a Service” or “SaaS” in which clients typically access software on the internet (via a web browser), and will typically pay by a subscription to use the service (which might also include file storage) The Application Service Provider (ASP) will build and maintain the infrastructure needed to host the software The ASP can update, test, and access user behavior – making it easier to identify areas that need improving The biggest criticism of SaaS is security
Once we have a new system, we also need to bring all of our previous data into the new system This is typically described as “data migration” – which is defined as “the process of transferring data between storage types, formats, or computer systems. It is a key consideration for any system implementation, upgrade, or consolidation” Problems that can arise: Corruption : data can become corrupted in transfer, data is unusable whilst being transferred, for large files this can be problematic as well as for files that people are likely to be using File Formats : the way one system saves a file in a format may not be compatible with the new system Date / Time / Currency / Language : the system of storing dates, times, currency, or even the international languages may not be compatible in data migration Cost : because in order to migrate data to new storage you have to own the new storage and you need to pay for enough storage for all your needs (which may not be possible) The system has been developed and tested , it is working correctly and doing everything that was agreed during the design stage. The business is waiting in eager anticipation for the new system to be handed over to them A key decision is which method of the four different methods of installation will be chosen, these are: Direct method : (or “plunge”) is where the company literally switches off the old system and switches on the new one Parallel method : is a more popular method than the previous one With a parallel changeover the organization runs both the old and new system in parallel for a time, then once the organization is sure that the new system is working properly and that staff are ready to begin using it they will make the decision to completely change over During a quiet period, perhaps during the night or at a weekend, the data is fully transferred from the old system which is then shut down Phased Changeover : is considered a compromise between parallel and direct changeovers In a phased changeover, the new system is implemented one stage at a time Advantages to phased changeovers are their low cost and isolated errors Disadvantage is the process takes a long time to complete because phases need to be implemented separately Pilot Changeover : the new system is tried out at a test site before launching it company- wide Since parallel changeovers tend to be expensive, using the pilot changeover technique allows companies to run the new system next to their old but on a much smaller scale This makes the pilot changeover method much more cost-effective After the kinks are worked out of the system at the test site, companies usually opt to use the direct changeover technique to launch the system company-wide USER FOCUS Moving away from analysis of the entire system, let us now focus on the individual users For our users, the new system can present challenges that can be addressed through documentation and training
- Viruses and Malware : which can do things like transfer (steal) personal data, to deleting everything on a hard drive (these include worms, Trojan horses, spyware, scareware, time bombs etc.) A Trojan Horse is a program that has the appearance of a useful and desired function but performs other undesired functions without you knowledge Worms are programs that enable the duplication and spread of copies of themselves throughout a system
- Hardware Malfunction : Some storage devices come with defects, and may be the cause of data loss, and these defects can be severe enough to cause the whole medium to 'fry' or just loss a small portion of the data
- Natural Disaster : where things such as earthquakes, floods, wars, etc. can destroy your hardware – they may also be caused by things like power failure, or fires (a little less„natural‟) Consequences of a data loss occurring. Medical Records : may result in serious consequences for the patient and the family, as medical records include data such as current or old diseases, allergies, vaccination and previous diseases or conditions that have run in your family – so if this data was lost it would cause a huge health risk to the patient Banking Records : banks still hold a lot of your personal information such as name, address, age, etc. and of course your bank accounts, so if this data is lost or stolen they will have access to all of that Government Agencies : will quite possibly be the sector that will own the most information regarding a certain individual, anything ranging from your address to your social security number and so on, and would cause serious social and security risks and damage if someone was to gain access of it Credit Card records : losing data may damage the company’s reputation, for example when companies like Amazon are hacked, important data like personal details and credit card information might be used against the users and this creates a feeling of insecurity between the company and the customers Privacy is a big issue with data loss, as customers information might be put available on the internet To try to prevent data loss, data backup systems are put in place – some examples include: Physical backups : using more than one physical devices like RAID (Redundant Array of Inexpensive Disks) drives where two copies of the data are held on two physical disks, and the data is always identical Online backups : or “cloud” backups, which work like physical backups but off site Antivirus software : to prevent malicious virus software from running on your computer and/or recover from it Physical security : by locking doors, or having somebody guarding the area where the data is stored can prevent somebody from physically stealing any data or having access to it where they could delete the data
SOFTWARE DEPLOYMENT
With all aspects of our system up and running, our software will still need updates and we need strategies for managing this: Application (“App”) updates : whenever the software is started, the updater will run, comparing the current version on the PC to the latest version that is on the internet, and if the internet version is newer than current local version, then the newest version will automatically be downloaded and installed (users can choose settings that they will be asked whether or not the update is allowed to take place) OS updates : it is also automated to occur (often at non-use hours like early in the morning) to protect the OS from cyber attacks as well as fix any software bugs or improvements – these are often categorized into critical and non-critical updates Java update : Java runs inside a “virtual machine” that allows Java software to be deployed to multiple platforms, but needs to often be updated (again automatically or through user choice) Hardware updates : often called “driver” updates or “firmware” updates help keep the specific hardware (e.g. video card, keyboard, printer, etc.) communicating and working (performing) properly – the problem with hardware updates is that they are not always automated and it forces the user to check the specific hardware’s website to see if an update is available
