Learning objective: gain appreciation for the complexity and fragility of
software that has to deal with times and dates in the real world.
This presentation homework is slide-only hand-in. We'll do live
presentations in class when students are called upon.
- You will be assigned a "group" on Canvas for this assignment (get
your assigned topic number from the People section on Canvas). However, this
is an INDIVIDUAL ASSIGNMENT. The "Group" is solely for
efficiently communication to each student which topic number from the list
below they are assigned. DO NOT communicate with any other student about
this assignment. (For group projects groups will indeed be groups; this
use of the Canvas group mechanism is a special case.)
- This is an INDIVIDUAL assignment completed by you and you
alone.
19-1. For the topic assigned below, find an example of a failure or
potential failure involving time or counter overflows, or other topics as
described. Some categories are finding a good example of a particular failure
mode (e.g., leap second), while other are finding a good example of any
time-related failure in a particular domain. Many of these will be discussed in
class, so if you see multiple examples on searches please try to look past the
first hit and pick one that you think is the most interesting to talk about in
class. Please make sure that your slides will be easily readable when displayed
in class, and be ready to give a 2 or 3 minute discussion of your topic in
class. Topics are assigned based on your sign-in number as below.
- 19-1a. First homework slide: a summary of the incident or mishap you
are covering:
- A title that indicates the name of the system or a generic description of
the defect
- A two to five bullet summary of the failure scenario. Briefly explain the
technical source of the problem as best you can. (This might require a bit more
searching than whatever the easiest to find article is. Use multiple references
if you have to.)
- What is the economic impact and/or safety impact of the failure?
- What could the designers have done to avoid the problem?
- A picture that illustrates either the application or the result of the
problem. A good illustration from a news article is fine, with a URL
attribution shown.
- 19-1b. For the second homework slide: a screen shot of important
pieces of an on-line description of the problem, including an attribution URL.
Don't include the whole article if it is so long that the fonts are too tiny to
read in a slide format. The headline and lead paragraphs describing the overall
situation are sufficient.
Topic assignments for this question are as below.If you have a strong
preference not to do a particular topic such as a personal experience with a
failure of this type, just let the instructor know and do either the topic
before or the topic after.
- Apple iOS DST alarm/reminder bug (pick your favorite; there are several to
choose from)
- Daylight savings time cell phone glitch (pick your favorite; there are
several to choose from)
- NASA Deep Impact NASA timer overflow
- Windows mobile 2010 bug
- 512K day (8/12/2014)
- Windows 95 timer rollover
- Excel 1900 bug
- Leap year Azure cloud
- Leap second Linux crash
- Jan. 1, 2010 Bank of Queensland eftpos terminal outage
- Dec. 2, 2017 iOS bug (version 11.1.2)
- Mar. 2018 European clocks lose time due to electricity grid disruption
- Jan. 2016 GPS timing melt-down
- Nov. 2018 Hospital record keeping and DST
- Oct. 2018 Hong Kong metro signalling crash
- Apr. 2019 NYCWiN and GPS rollover
- Apr. 2019 Honeywell aircraft GPS rollover
- Jun. 2019 Collins GPS leap second
- Jul. 2019 Airbus A350 reboots
- Dec. 2021 Google Chrome version 100
- Jan. 2022 MS Exchange 2201010001 overflow
- Jan. 2022 Honda clock bug
- Oct. 2024 1700 identical tax letters in Germany
- 2038 Unix rollover
Rubric:
- First slide: Title, summary, economic impact, avoidance, picture
- Second slide: sources & attribution
- Format per HW #1. Page size and font size requirements are strictly
required!
Supplemental Materials