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Chapter 10. Phase Description. Systems Operation, Support, and Security is the final phase in the systems development life cycle (SDLC) You will be supporting a functioning information system
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Phase Description • Systems Operation, Support, and Security is the final phase in the systems development life cycle (SDLC) • You will be supporting a functioning information system • You continuously will assess and improve the system, and you will be alert to any signs of obsolescence • You will also address multi-level security issues
Chapter Objectives • Explain how the systems operation, support, and security phase relates to the rest of the system development process • Describe user support activities, including user training and help desks • Discuss the four main types of system maintenance: corrective, adaptive, perfective, and preventive
Chapter Objectives • Explain various techniques for managing systems operation and support • Describe techniques for managing system performance, including workload measurement and capacity planning • Assess system security at five levels: physical security, network security, application security, file security, and user security
Chapter Objectives • List factors indicating that a system has reached the end of its useful life • Assess future challenges for IT professionals as technology reshapes the workplace
Introduction • Now that the system is operational, the real key question is whether or not the system meets user expectations, supports business objectives, and is secure • Systems must be maintained and improved continuously to meet changing business demands, and users constantly require assistance
Overview of Systems Support and Maintenance • The systems operation, support, and security phase begins when a system becomes operational and continues until the system reaches the end of its useful life • After delivering the system, the analyst has two other important tasks: he or she must support users and provide necessary maintenance to keep the system operating properly
User Support Activities • User Training • In addition to the initial training that is performed when a new system is introduced • New employees must learn how to use the company’s information systems • User training package • Training users about system changes is similar to initial training
User Support Activities • Help Desks • Also called information center (IC) • Enhance productivity and improve utilization of a company’s information resources • Might have to perform the following tasks: • Show a user how to create a data query or report that displays specific business information • Resolve network access or password problems • Demonstrate an advanced feature of a system or a commercial package • Help a user recover damaged data
User Support Activities • Online Chat Support • Interactive support also can be delivered in the form of an online chat • Virtual Classroom
Maintenance Activities • The systems operation, support, and security phase is an important component of TCO (total cost of ownership) because ongoing maintenance expenses can determine the economic life of a system • Operational costs • Maintenance expenses • Maintenance activities
Maintenance Activities • Corrective Maintenance • Diagnoses and corrects errors in an operational system • Can respond to errors in various ways, depending on nature and severity of the problem • In a typical procedure, a user submits a systems request that is evaluated, prioritized, and scheduled
Maintenance Activities • Adaptive Maintenance • Adds enhancements to an operational system and makes the system easier to use • The procedure for minor adaptive maintenance is similar to routine corrective maintenance • Can be more difficult than new systems development because the enhancements must work within constraints of an existing system
Maintenance Activities • Perfective Maintenance • Involves changing an operational system to make it more efficient, reliable, or maintainable • Can improve system reliability • Cost-effective during the middle of the system’s operational life
Maintenance Activities • Perfective Maintenance • Software reengineering • Depending on results of software reengineering, the system might be revised, migrated to a different environment, or replaced altogether • Programs that need a large number of maintenance changes usually are good candidates for reengineering
Maintenance Activities • Preventive Maintenance • Requires analysis of areas where trouble is likely to occur • IT department normally initiates preventative maintenance • Often results in increased user satisfaction, decreased downtime, and reduced TCO • Sometimes does not receive the high priority it deserves
Managing System Support • Maintenance Team • System administrator • Systems analysts • Analysis • Synthesis • Programmers • Applications programmer • Systems programmer • Database programmer • Programmer/analyst
Managing System Support • Maintenance Team • Organizational issues • IT managers often divide systems analysts and programmers into two groups: one group performs new system development, and the other group handles all maintenance • Many analysts feel that maintenance work is less attractive than developing new systems • One disadvantage of rotation is that it increases overhead costs
Managing System Support • Managing Maintenance Requests • Involves a number of steps • Maintenance request • Initial determination • Role of the systems review committee • Completion of the work • User notification
Managing System Support • Establishing Priorities • Systems review committee separates maintenance requests from new systems development requests when evaluating requests and setting priorities • Many IT managers believe that evaluating projects together leads to the best possible decisions • Neither approach guarantees an ideal allocation between maintenance and new systems development
Managing System Support • Configuration Management • Configuration management (CM) • As enterprise-wide information systems grow more complex, configuration management becomes critical • Most maintenance projects require documentation changes
Managing System Support • Maintenance Releases • Maintenance release methodology • Maintenance release • A numbering pattern distinguishes the different releases • Reduces the documentation burden • New features or upgrades are available less often • Service packs
Managing Systems Support • Version Control • Version control is the process of tracking system releases • Systems librarian • Archived • Baselines • Functional baseline • Allocated baseline • Product baseline
Managing System Performance • A system’s performance directly affects users who rely on it to perform their job functions • To ensure satisfactory support for business operations, the IT department monitors current system performance and anticipates future needs • Benchmark testing
Managing System Performance • Performance and Workload Measurement • Response time • Bandwidth and throughput • Kbps (kilobits per second) • Mbps (megabits per second) • Gbps (gigabits per second)
Managing System Performance • Performance and Workload Measurement • Turnaround time • Capacity Planning • What-if analysis • You need detailed information about the number of transactions; the daily, weekly, or monthly transaction patterns; the number of queries; and the number, type, and size of all generated reports
Managing System Performance • Capacity Planning
Managing System Performance • System Maintenance Tools • Many CASE tools include system evaluation and maintenance features • In addition to CASE tools, you also can use spreadsheet and presentation software to calculate trends, perform what-if analyses, and create attractive charts and graphs to display the results
System Security • Physical Security • First level of security concerns the physical environment • Computer room • Physical access to a computer represents an entry point into the system and must be controlled and protected
System Security • Physical Security • Computer room security • Biometric scanning systems • Motion sensor • Servers and desktop computers • Keystroke logger • Tamper-evident cases • BIOS-level password • Boot-level password • Power-on password
System Security • Physical Security • Notebook computers • Select an operating system that allows secure logons and BIOS-level passwords • Mark or engrave the computer’s case with the company name and address, or attach a tamper-proof asset ID tag • Universal Security Slot (USS) • Back up all vital data
System Security • Physical Security • Notebook computers • Use tracking software • While traveling, try to be alert to potential high-risk situations • Establish stringent password protection policies
System Security • Network Security • Network • Traffic • Network interface • Encrypted
System Security • Network Security • Encrypting network traffic • Unencrypted – plain text • Public key encryption (PKE) • Public key • Private key • Wi-Fi Protected Access (WPA) • Wired Equivalent Privacy (WEP)
System Security • Network Security • Private networks • Virtual private networks • Virtual private network (VPN) • Tunnel
System Security • Network Security • Ports and services • Port • Destination port • Service • Port scans • Denial of service (DOS) • Distributed denial of service (DDOS)
System Security • Network Security • Firewalls • Firewall • Rules – protocols • Firewalls can be configured to detect and respond to DOS attacks, port scans, and other suspicious activity
System Security • Application Security • Services • Security hole • Administrator – super-user • Permissions • Input validation • Patches and updates • Patches • Third-party software • Automatic update service
System Security • File Security • Safety and protection of files is a vital element in any computer security program • Permissions • User Groups
System Security • User Security • Privilege escalation attack • Identity management • Password protection • AOL PassCode® • Social engineering • User resistance
Backup and Disaster Recovery • The heightened focus on disaster recovery has spawned a whole new disaster recovery industry, which includes many new tools and techniques
System Obsolescence • Even with solid support, at some point every system becomes obsolete • Signs: • The system’s maintenance history indicates that adaptive and corrective maintenance is increasing steadily • Operational costs or execution times are increasing rapidly, and routine perfective maintenance does not reverse or slow the trend
System Obsolescence • Signs: • A software package is available that provides the same or additional services faster, better, and less expensively than the current system • New technology offers a way to perform the same or additional functions more efficiently • Maintenance changes or additions are difficult and expensive to perform • Users request significant new features to support business requirements
System Obsolescence • Systems operation and support continues until a replacement system is installed • At some point in a system’s operational life, maintenance costs start to increase, users begin to ask for more features and capability, new systems requests are submitted, and the SDLC begins again
Facing the Future: Challenges and Opportunities • Predictions • It is clear that companies will continue to face intense competition and global change, especially in the wake of economic, social, and political uncertainty • It is interesting to note that some observers, such as Bill Joy, wonder whether technology is moving so fast that humans will be left behind • What does seem clear is that the future world of IT must be envisioned, planned, and created by skilled professionals
Strategic Planning for IT Professionals • An IT professional should think of himself or herself as a business corporation that has certain assets, potential liabilities, and specific goals • Working backwards from your long-term goals, you can develop intermediate mile- stones and begin to manage your career just as you would manage an IT project • Planning a career is not unlike planting a tree that takes several years to reach a certain height
IT Credentials and Certification • Credentials • Certification • Many IT industry leaders offer certification, including Microsoft, Cisco, Novell, Oracle, and Sun Microsystems
Chapter Summary • Systems operation, security, and support covers the entire period from the implementation of an information system until the system no longer is used • A systems analyst’s primary involvement with an operational system is to manage and solve user support requests • A maintenance team consists of one or more systems analysts and programmers
Chapter Summary • Systems analysts need the same talents and abilities for maintenance work as they use when developing a new system • Configuration management is necessary to handle maintenance requests • System performance measurements include response time, bandwidth, throughput, and turnaround time • All information systems eventually become obsolete
Chapter Summary • An IT professional should have a strategic career plan that includes long-term goals and intermediate milestones • An important element of a personal strategic plan is the acquisition of IT credentials and certifications that document specific knowledge and skills • Chapter 10 complete