Ch 11: Creating Invormation Systems Flashcards
Custom Development- Necessity
In some cases, custom developing the software is not an option for your firm, it’s a necessity
Custom Development- example Amazon
Amazon first introduced their software for personal recommendation system when ecommerce was largely uncharted territory. Waiting for an off the shelf product was not an option
Advantages of Custom Development- Unique tailoring
Custom made software, like a tailor made suit, can be designed to fit perfectly with the organizations characteristics and needs
Advantages of Custom Development- Unique tailoring example
Lands End metaphor “Fitting 100 some million women in the US in 8 or 10 sizes as well as the would like is really impossible. “ Typically when people purchase clothing they accept a substandard fit.
Advantages of Custom Development Make vs. Buy- Unique tailoring- Competitive advantage
While certain software will work across the board in all industries, business processes are unique to each business and custom software becomes a source of competitive advantage. Store bought software can undermine a company’s uniqueness and be detriment
Advantages of Custom Development- Flexibility and Control
Custom software provides highest level of flexibility and control to an organization. Building from scratch allows the developers to mold it into any form. It also allows the program to modified and/or evolved at any time.
Advantages of Custom Development- Flexibility and Control- Store Bought
The level of control is unachievable with store bought software as they are intended to serve the needs of a large number of buyers. Typically they have broad appeal and lack the niche requests necessary of some companies.
Advantages of Purchasing- Overview
Off-the shelf products have become very comprehensive and tend to yield a number of advantages.
Advantages of Purchasing- Faster Rollout
How quickly a firm can be up and running is a major factor in the decision process of new software. Purchased software dramatically decreases the time necessary to implement. Once purchased, implementation process is ready to start
Advantages of Purchasing- Knowledge Infusion
The concept of knowledge infusion is now an important design and marketing tool for software vendors who proactively seek out best practices in order to code them into the applications. These benefits are more visible when a software is designed for a sp
Advantages of Purchasing- Economically Attractive
Purchasing off-the-shelf typically allows the firm seeking new software to capitalize on economies of scale by purchasing through a vendor. Since these vendor see declining fixed costs, they in turn offer a lower unit cost.
Advantages of Purchasing- High Quality
Skeptics point out that pre-packaged software generally have a lot of bugs. Yet the software companies will point out the sizable testing budgets and large installed base of users as evidence that their product has been tested and all problems have surfa
The SDLC model and why it is called “water fall”
The SDLC is a highly structured methodology where the outputs of one stage become the inputs of the next, and where the project team strives to keep changes after the project has started to a minimum. The SDLC is often called the waterfall model because, as water flowing down a waterfall never flows upward, there should be no going back once a stage has been completed.
What are the steps involved in Defining, Building, and Implementing information systems?
Definition:
Investigation,Feasibility Analysis, System Analysis
Build:
System design, Programming,
Testing
Implementation:
Installation, Operations, Maintenance
Definition: Investigation
During investigation, proponents of the new system must identify what business issues the system will pertain to. Managers formulate the main goals, scope, and value proposition of the new system.
Definition: Feasibility Analysis
In order to ensure that scarce organizational resources are put to best use, the project team must heavily scrutinize the proposed project prior to giving the formal go-ahead. Specifically, the team must evaluate the technical, operational, and economic feasibility of the project.
Definition: System Analysis
Once a decision has been made that the system is worth pursuing, the project team needs to identify and articulate the system requirements. Systems analysts and the stakeholders take center stage at this point.
Build: System Design
Taking the results of the definition phase, architects create the structure of the system. The team identifies what hardware will be used, what languages will be adopted, what data structures are needed, and so on. The output is a precise set of documents
Build: Programming
Programming is the process of translating the abstract software design into a set of commands or instructions that can be executed by the hardware. If the application requires the creation of new databases, their structure is also developed at this stage.
Build: Testing
Formalized assessment of components and subsequently of the complete applications is an essential stage in the SDLC. This phase is articulated in alpha testing, carried out by developers themselves, and beta testing, carried out by releasing the beat vers
Implementation: Installation
Installation typically takes place during slow periods for the organization. If possible it is completed when not in use, i.e. weekend or nights. If an existing system is being replaced, the firm migrates from the old one to the new on following on of t
Implementation: Operations
The system is up and running, and the organization begins to use it. The project team is disbanded and the new system becomes a permanent asset of the firm to be maintained and managed.
Implementation: Maitenance
Once the system is in place, and is up and running, both errors that had escaped the testing phase and enhancements that had escaped the requirements definiton phase begin to emerge. The process of compiling this information, prioritizing requests, and im
Implementation: Installation
Installation typically takes place during slow periods for the organization. If possible it is completed when not in use, i.e. weekend or nights. If an existing system is being replaced, the firm migrates from the old one to the new on following on of t
The four Installation approaches- Parallel
The old and new systems run together for a period of time. This is a conservative method and it offers insurance against failure of the new application. It is the most costly as it requires the redundancy of efforts. Some times this is the only option,
The four Installation approaches- Direct
The old system becomes discontinued and firm cuts over to the new one. Most radical approach but sometimes cannot be avoided. Or the previous system stops functioning
The four Installation approaches- Phased
The new system progressively replaces the functionalities of the old one. This approach is best suited to modular or componentizes applications that can be rolled out in stages.
The four Installation approaches- Pilot
Well suited for multiunit operations (i.e. hotels, chain retailers), this approach allows the firm to run the new system in one business unit or in one of the firms departments before rolling it out completely.
Phases of the systems selection process
Definition, Build, Implementation
Phases of the systems selection process - Definition
Investigation, Feasibility Analysis, System Analysis, Formulate Evaluation Criteria, Compile Short List of Vendors, Compile and Distribute RFP, Evaluate Alternatives, Negotiate Contract
Phases of the systems selection process - Build
System Design (Customizations), Programming (Customizations), Testing
Phases of the systems selection process - Implementation
Installation, Operations, Maintenance
