Topics of Discussion
l History
l Issues
l Solutions
l Complicating
Factors
l Implications
l Lessons
Facets of the Issue
l
Limits to system date data
types in hardware registers
l Software
date data types increment, fill storage register, and FAIL
l Problem
plagued many GPS receivers on August 21, 1999
Facets of the Issue
l
Hard coding dates and magic
numbers
l Hard
coding values
l “Magic
Numbers“
l Date
comparison failures
Facets of the Issue
l
Leap Year Calculations
§
Year 2000 is a leap year
§
Gregorian Calendar rules
Facets of the Issue
l
Two digit year
representation results in six digit date coding
l Expected
to be most prevalent year 2000 failure
l Inability
to distinguish between 1900 and 2000
l Administrative
systems
A Variety of Solutions
l
Different solutions for
different computing contexts
l
Expanding the year field to
four digits
l Complete
solution
l Large
internal task
l Check
other systems that provide input
A Variety of Solutions
l
Encode century information
in six digits in at least five ways
l Encode
full Julian dates
l Use
two 8-bit year fields
l Replace
month with single digit for century
l Represent
month as a character field
l Store
date as an increment
A Variety of Solutions
l
Logic Windows
Ø Compare
value in two digit field against application window
Ø No
data changes required
Ø Permanent
solution; extend window indefinitely
Ø Evade
massive changes
A Variety of Solutions
l
Data Bridges
l Very
popular solution
l Convert
applications to four digit year
l Translation
between different date representations takes place
A Variety of Solutions
l
System clock reversal and
28 year time bridge implementation
l Source
code unavailable
l Scripts
that output correct date
l Replacing
or retiring the system
l Upgrade
to Y2K complaint system
l Merge
with a company that already has Y2K complaint systems
A Variety of Solutions
l
Take no action
l No
problems or causes minor problems that users can deal with
A Variety of Solutions
l Test
all solutions
l Rigorous
testing of date-inputting systems must occur!
l Validate
full compliance
Complicating Factors
l
Issue is unprecedented
l No
technological failure has been so expansive and held disastrous consequences
l Businesses
scramble for solutions
l 73%
of small businesses have no contingency plans, as opposed to 25% for larger enterprises
(CNNfn, May 14, 1999)
l General
lack of knowledge allows scams
Complicating Factors
l
Myth: Y2K failures are
purely software glitches
l Embedded
systems
Complicating Factors
l Myth:
Y2K failures are purely software glitches
l “World's
biggest Easter egg hunt"
l Repairing
or replacing these microchips may be difficult
Complicating Factors
l
All systems that use dates
may potentially fail
l Assuming
that a recently released product is Y2K-ready may be dangerous
l Trusting
a vendor's word may also prove costly
Complicating Factors
l System
to system interactions
l Co-dependent
systems must be fixed simultaneously
Complicating Factors
l Resource
Scarcity
l Dearth
of professionals who can make headway with this problem
l Overall
challenge posed by issue
l No
"cookie-cutter" solution; "Where is the problem, and what are the fixes?“
Implications
l Recent
senate report says US has made "remarkable progress"
l Utilities,
banks, aviation, and large medical services shall remain functional
l Local
and state governments, poor hospitals, school districts, and small businesses lag behind
l Russia,
China, and Italy were condemned the most harshly
l Russia
Y2K nuclear missile woes
Lessons Learned
l What
are the lessons we have learned from the Y2K bug?
Q & A
Appendix A
l Breakdown
of embedded systems problems by IEEE
Appendix B