System Changeover

1
System Changeover
2
Changeover Process

• Scheduling process
• Weekends, nights, or holidays
• Notification to customers
• external
• internal
• Activity phase-down
• only priority transactions

3
Changeover Process

• File conversion
• download old system
• upload new system
• System cut-over
• New system priming
• start feeding transactions

4
File Conversion

• Example of effort
• 5000 records
• 300 character per record
• 1.5 million characters to enter
• at 1200 error-free keystrokes per minute
• 208 days, or 41.6 work weeks

5
File Conversion

• Some conversion done by writing conversion
  programs
• old record format to new
• But new records are always enhanced
• new fields
• modified fields (e.g., length)

6
System Cut-Over

• Types of cut-over tactics
• parallel
• crash
• staged
• includes pilot

7
Parallel Cut-Over
OLD SYSTEM
NEW SYSTEM
Parallel Period
8
Crash-Cut-Over
OLD SYSTEM
NEW SYSTEM
Cut-over Date
9
Staged Cut-Over
O L D
N E W
10
Cut-Over Factors

• Costs
• System criticality
• User computer experience
• System complexity
• User resistance