Software Processes & Project Management
Case studies Copyright University of Melbourne 2021-2022
School of Computing and Information Systems
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The University of Melbourne 2022 – Semester 1 Week 10
Case Studies
Today we will look at two areas of case studies.
• This is a teaching case study, based on a real case.
– Ranganathan, C., Krishnan, P., & Glickman, R. (2007). Crafting and executing an offshore IT sourcing strategy: GlobShop’s experience. Journal of Information Technology, 22(4), 440-450.
– Some parts of what is in the journal article are not relevant to this course, so we don’t discuss it here.
Quality Management Case Studies
• Here we will discuss some example situations where quality management concepts were not followed well, sometimes with very bad consequences.
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Case Studies
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Case study
Overview of GlobShop Company
• Global travel-retail company. Based in USA.
• $5 billion business.
– Quite large
• 200 duty-free and general merchandise shops in airports, hotel lobbies in Asia, Australia, North America and Europe.
• Cost savings and reduction due to 11 September 2011.
– Yes, this is a while ago. But the lessons learnt can be applicable still. E.g. during COVID-19 there was reduced travel, just like after 11 September 2011.
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Case study
GlobShop: Problems
• IT was highly decentralised
– multiple versions of the same application
• Each region had its own data centre
• Different applications that did the same
– e.g. two different point of sales
GlobShop: What did they do?
• Globshop decided to centralise and outsource.
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Case study
GlobShop: Need to decide how to outsource
• Choose what to outsource, which vendor.
• What type of sourcing arrangement, managing vendor relationship, change management issues.
– How to transition existing business structure to new structure.
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Case study
GlobShop: Considering options
Who to outsource to?
– nearshoring
• Eastern Europe – unstable
– lack of many suitable options
– mature segment with many players – tier1
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Case study
GlobShop: Decision
Decided to outsource to ISS (Indian vendor)
• Medium sized, yet growing (not tier-1).
• Valued client, not one of many.
– If they went with a large vendor, Globshop may not be as valued by the vendor.
• Hybrid offshore
– Presence both in India and USA. Could be quite useful.
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Case study
GlobShop – ISS
Globshop had a lot of IT projects, applications, infrastructure, data centres.
They needed to decide how to cost everything.
Fixed price for a development project was selected as • Requirements were well spec-ed and project understood.
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Case study
GlobShop – ISS
• Master Service level agreements for 3 Service Level agreements (SLA).
– An SLA is a type of contract, setting out what they agree to.
• E.g. how long to answer service requests, how many hours can there be downtime before there is a penalty.
– Gave more flexibility. Allowed each group to be focused.
• Different staffing models, rate structures and service level for each SLA.
• There were separate agreements for consolidation, maintenance and ongoing
support for core merchandising systems, including support for:
– Enterprise Resource Planning modules,
– Point of sale systems
– Intranet development
– Content management systems
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Case study
RELATIONSHIPS
GlobShop- Internal employees
• Needed to ensure that employees helped with transition to ISS. – May have push back from employees.
• Redundancies, but needed knowledge transfer.
– Can’t suddenly change to ISS. Need knowledge transfer to occur.
• Phased redundancies.
– Uncertainty for staff and Globshop.
• Increased bonuses for staying.
• Helped employees with job search.
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Case study
RELATIONSHIPS
GlobShop- ISS employees
• Tight partnership to ensure value add
• Created teams- Communities of Practice (COP)
• Different entities with specific focus of expertise (Business, IT and offshore vendor)
• Viewed as internal colleagues
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Case study
Near the end of 3 year contract….
• Should outsource more?
• Renew contract?
• ISS had grown, had several Fortune 1000 companies
• Transfer of contacts, account managers, star employees to more prestigious clients
• Too risky to be reliant on one company
• Any internal IT dept.
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Case Study
Quality Management Case Studies
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Software Quality
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What do these movies have in common?
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Quality- Case study
The characters make huge amounts of money by taking advantage of the fact that numbers need to be shortened to two decimal places in order to function as currency, in dollars and cents.
• round(), which rounds to the nearest cent, or
• floor(), which just cuts off all the extra decimal places.
For example, an after-tax salary computation of $145.459 would normally be rounded to $145.46; floored to $145.45
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Stock exchange
• Sometimes fractional cents aren’t stolen—they vanish.
• Early 1980s, a new stock index at the Vancouver Stock Exchange tracked
a steady and mysterious loss in value.
• An investigation revealed that floor() was being used instead of round().
• Lost fractions of cents accumulating to almost a 50 percent loss of value in 22 months.
• The programming mistake was finally fixed; the index closed around 500 on a Friday and reopened the following Monday at over 1,000, the lost value restored.
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• Parliamentary election rule that parties must surpass a minimum 5-percent threshold in order to receive a seat/s in the legislature.
• April 1992 elections in the state of Schleswig-Holstein, had received exactly 5 percent of the votes.
• After the election results were published, discovered that the Greens had received only 4.97 percent of the vote.
– Rounding Error!
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June 1996, when the European Space Agency’s
• Ariane 5 rocket exploded just 39 seconds after lift-off.
• After a decade of development
• Cost $7 billion,
• Destroyed payload of four uninsured scientific satellites across mangrove swamps, resulting in the loss of $500 million worth of equipment.
• Rocket blew up because made an abrupt attempt to correct and compensate for wrong turn—a turn it had not, in fact, taken.
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• This confusion was caused by a rounding error in the inertial reference code that was being reused from the Ariane 4 rocket.
• A 64-bit floating point number representing the horizontal velocity was converted to a 16-bit signed integer,
• 48 fewer number places.
• Mistake because Ariane 5 was much faster than Ariane 4.
• The conversion yielded a number that was larger than the largest possible number in that quantized representation from the slower Ariane 4.
• Caused an error message to be transmitted
• Interpreted as a nonsensical number by the on-board computer—and disaster
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What should they have done?
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Quality Management Process
Quality Assurance
Quality Planning
Quality Control
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Quality Management Process
Quality assurance:
The establishment of a framework of organizational procedures and standards that lead to high-quality software
Quality planning:
The selection of appropriate procedures and standards from the framework, adopted for the specific project
Quality control:
Ensuring that the software development team has followed the project quality procedures and standards
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Technical Reviews
Informal Reviews Formal Reviews Walk throughs Code inspections Audits
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• In the years leading up to the year 2000, companies spent a lot of money fixing this issue.
• Did you know the Year 2038 problem exists?
– Unix time – the number of seconds elapsed since the Unix epoch (00:00:00 UTC on 1 January 1970)
• Stored in a signed 32-bit integer. Stores max value of 2,147,483,647.
• What happens after 2,147,483,647 seconds (68 years)?
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What is a bug/debugging
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FUN FACTS: Bugs
• Account by computer pioneer , who publicized the cause of a malfunction in an early electromechanical computer.
• worked at Harvard Faculty at the Computation Laboratory where she continued her work on the I and II
• Operators traced an error in the I to a moth trapped in a relay, coining the term bug.
• This bug was carefully removed & taped to the log book. This was the first bug, today we call errors or glitches in a program a bug.
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References
1. Movie pictures retrieved from imdb.com
2. Rounding errors
https://slate.com/technology/2019/10/round-floor-software-errors-stock-market- battlefield.html
3. SoftwareBug
https://en.wikipedia.org/wiki/Software_bug#:~:text=The%20term%20%22bug%22%20was% 20used,in%20an%20early%20electromechanical%20computer.&text=Operators%20traced% 20an%20error%20in,taped%20to%20the%20log%20book.
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