Solution session 6
Q1 What is SDLC and what applications are most suitable for it?
Briefly describe six SDLC steps you will use designing a web-based inventory system
SDLC is a traditional system development life cycle used mostly for structured and well defined tasks. It consists of six steps (see page 277).
SDLC can be time consuming resulting in a system that is complete but may take over one to two years to develop. It is likely that SDLC is
combined with other development methodologies like prototyping and/or eXtreme Programming (XP) methodology (see page 284) to make it more useful in digital world
where time is money..
Web-based inventory system:
Planning: Define the scope the system. Is it based for a single department/ many departments? Does it include supplier also? Is it feasible economically, technically, politically, legally etc.
Analysis: Survey the users, clerks, supervisors who will be using this system. Define what users need. This stage provides overall specs for the system. What data is required, what kind of screens are required etc. Perform cost/benefit analysis to ensure feasibility of the procurement system
Design: Develop design of the system. How inventory order will work in relation to production, marketing etc. What hardware/software and what platform is needed to provide desired web-based
Capabilities. Develop entity relationship models.
Development: This implies actual implementation of the system in a specific hardware/software and a platform. Build the infrastructure , develop database, load inventory data
Testing: test for all bugs, perform test runs on partial/complete web systems. Make up inventory and demand data and test system robustness
Implementation: Once system is satisfactory and test is complete, implement it using one of the techniques described on page 281. Since this is web-based system, it should be implemented as pilot (if a system already exists) or as a plunge system if no system exists.
Maintenance:
Provide 24/7 support, update system as needed
Q2
You have a medium size business with $100M turnover. you need to develop a web-based procurement system. You have to decide between
in-house--develop it yourself
in-sourcing --within your company--contract it out to your MIS department
out-sourcing--within USA--contract to a company like EDS, IBM
near sourcing--to Mexico, Canada
Off-shoring--to India, China etc..
Since this is a medium size business, it is relatively small for off-shoring. Company must keep control of its cost. It is not desirable to outsource to a big company like IBM or EDS. Big companies maynot be interested in providing customized products.
It is recommended that company should near shore to Canada or Mexico if it does not have inside expertise.
This will keep travel costs low and will allow for better and quick cooperation between the companies.
What are the factors you would consider and why? What would be your ultimate decision? Support your answer.
Some of the factors to consider would be:
Cost
Reputation of the company
Past experience with similar assignments
Company personnel experience and qualifications
Language problems, if any
Q3
Your MIS department has just developed a web-based CRM system. How should they implement (phased, crash, pilot etc..) it in your department? what factors should they consider?
If the company does not have a current system, then it would be implemented as a plunge system since there is nothing to replace. However if the system is mission critical, it maybe better to implement
One piece at a time so as not to disturb the entire process in case of flaws in the new system.
If the company currently does have a procurement system, then use a “pilot” approach. Implement one piece at a time and then keep expanding as users become comfortable with each piece of the new system. You do not want to replace a mission critical system with a completely new system, especially in a web environment. A failure could be detrimental or even fatal to your business.
Q4What is prototyping? What's the difference between a prototype and simulation model (like Boeing uses it to train their pilots)?
How is SDLC different than prototyping?
Prototyping allows to build a “quick” and “dirty” usable system. Users can see immediate benefit of the system. Initial prototype maybe developed with a day. Users are continuously involved in
Testing/developing the system. Simulation models mimic a real life model or situation where as prototyping is a methodology to build systems. Prototyping maybe used to build simulators.
Prototyping is a “quick” approach. All steps of SDLC maybe embedded in each step of prototyping. Users are constantly involved in prototyping. However, prototype may produce sub optimal systems since they use “bottom-up” approach. I.e., start with end user(s) and create system for current users, whereas SDLC may use top down approach, start with the macro approach for the whole organization. SDLC is used for structured tasks whereas prototyping is used for unstructured or one time tasks.
Q5: Cloud Computing
NIST defines cloud computing as a “ model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. This cloud model promotes availability and is composed of five essential characteristics, three service models, and four deployment models”.
The simple notion of “pay what you use” is behind this computing revolution. This says companies do not have to have their own servers or even computing centers. They borrow computing power and pay for what they use. It is similar, in principle, to your household usage of electricity. Y only pay for the electricity that you use, you do not have the generator and other equipment to generate electricity. Similarly organizations can cut costs since they do not need computing servers or even centers.