Systems Architecture, Seventh Edition Chapter 1 Computer Technology: Your Need to Know ©2016. Cengage Learning. All rights reserved.

Chapter Objectives In this chapter, you will learn to: Define systems architecture and related terms Explain the relationship between architecture, design, and technology Describe what technology knowledge is required to develop information systems and manage computing resources Describe sources of architecture- and technology-related knowledge and how to effectively use each ©2016. Cengage Learning. All rights reserved.

Rapid Technology Developments Moore's Law is the empirical observation: the number of transistors on an integrated circuit (for minimum component cost) doubles every 24 months. -- Gordon Moore, 1965

Computing Devices are Everywhere Increasingly complex and powerful And yet easier to use

Systems Architecture and Related Terms Systems architecture―structure, interaction, and technology of computer or information system components Computer architecture—Architecture of a single computer system or a group of cooperating computer systems Information architecture—Architecture of data or information—for example, a database schema or the structure of a document archive Network architecture—Architecture of a computer network including wired and wireless connections, network-specific hardware such as routers, and related communication protocols and software Software architecture—Architecture of a program, software subsystem, or software system Technology architecture—Combination of all of the above with specific emphasis on issues such as performance, reliability, compatibility, and extensibility ©2016. Cengage Learning. All rights reserved.

Technology Knowledge Requirements Technologically complex devices are all around us, for example: Automobiles Cell phones Home theatre systems Computers Most technologically complex devices are: Relatively simple to operate Successful operations requires little knowledge of their “internals” or underlying technology So if devices can be easily used without knowing their inner details, why study those inner details? ©2016. Cengage Learning. All rights reserved.

Knowledge Requirements for Acquisition Knowledge requirements for acquisition are higher than for ordinary day-to-day use, for example consider a laptop purchase scenario: How much memory is required? Is an Intel processor required or will and AMD work just as well? How much disk space do I need today? Next month? Next year? Is the built-in graphics chip-set sufficient or do I need an upgrade? Can the system be expanded to meet my needs next year? In two or three years? Answering such questions requires knowledge of your needs, the underlying technological alternatives, and the compatibility (or lack thereof) among the needs and alternatives The technical language can be complex (e.g., Core i7, 802.11n, DDR3, GHz, TB, serial-attached-SCSI, RAID) ©2016. Cengage Learning. All rights reserved.

Knowledge Requirements for Configuration Knowledge requirements for configuration are higher than for acquisition and ordinary day-to-day use, for example: Can I expand memory capacity to 8 GB? If so, what specific memory devices are required to do so? If there are multiple choices are the more expensive ones worth the extra cost? My laptop meets the minimum requirements for Windows 7 but it runs sluggishly? Can I improve performance without upgrading hardware? I need to connect from home to my work computer through a VPN – how do I configure the connection? I can’t communicate with other players while running a multiplayer game that I just installed. Is this a firewall problem? If so, how do I configure the firewall to enable the game without compromising system security? ©2016. Cengage Learning. All rights reserved.

Information System Development Information system development follows a system development life cycle (SDLC) The Unified Process (UP) is the most commonly-used SDLC today Two key UP concepts: Discipline: A set of related activities of similar type and skill requirements Iteration: A relatively short time duration during which a mix of UP activities are performed to produce one or more specific deliverables ©2016. Cengage Learning. All rights reserved.

UP Disciplines and Iterations FIGURE 1.2 Disciplines and iterations in the Unified Process Courtesy of Course Technology/Cengage Learning ©2016. Cengage Learning. All rights reserved.

UP Disciplines Technical Knowledge Requirements Business modeling discipline Construct and validate models of the business (e.g., narratives, organization charts, workflow diagrams) Technical knowledge requirements are relatively low unless the business is technology-oriented (e.g., aircraft manufacturing or software development) Requirements discipline Construct and validate models of one or more systems that solve specific problems or implement specific functions (e.g., workflow, network, and class diagrams) Technology knowledge requirements are usually low ©2016. Cengage Learning. All rights reserved.

UP Disciplines Technical Knowledge Requirements - Continued Design discipline Architectural design – what are the required software, hardware, and network components, and how do they interact? Detailed design – specify the internal details of specific components such as databases, software modules, and user interfaces Technical knowledge requirements for both types of design are high Broader knowledge required for architectural design Deeper (more specialized) knowledge required for detailed design ©2016. Cengage Learning. All rights reserved.

UP Disciplines Technical Knowledge Requirements - Continued FIGURE 1.3 Design activities in the Unified Process Courtesy of Course Technology/Cengage Learning ©2016. Cengage Learning. All rights reserved.

UP Disciplines Technical Knowledge Requirements - Continued Implementation discipline Build (or acquire) and assemble components into a functional system Technical knowledge requirements are very high (e.g., programming languages, operating systems, database management systems, network protocols, and security measures) This is similar to configuration as described earlier Testing discipline Test functional system against requirements and make needed corrections Must understand technical “innards” and interaction among components to diagnose problems, evaluate corrective measure(s), and implement them ©2016. Cengage Learning. All rights reserved.

UP Disciplines Technical Knowledge Requirements - Continued Deployment discipline Transfer the “bench tested” system into a production environment and test it against “live-use” requirements Technical knowledge requirements are similar to implementation and testing disciplines ©2016. Cengage Learning. All rights reserved.

Other Technical Knowledge Requirements System Evaluation and Maintenance Examples include upgrading capacity, adding/modifying functions, and porting existing systems to new operational environments Requires broad technical knowledge for planning/evaluation and deep technical knowledge to implement changes Managing Computing Resources (e.g., CIO) Requires broad technical knowledge – sufficient to understand and evaluate technology alternatives Requires ability to interact with technical specialists and to speak/understand their language. ©2016. Cengage Learning. All rights reserved.

Roles and Job Titles Classification of computer professionals Software developers Systems programmers Hardware personnel Systems managers Computer hardware and software knowledge requirements of each group ©2016. Cengage Learning. All rights reserved.

Information Sources Technical knowledge gained in this course is a foundation But it will erode quickly because computer and information technologies change rapidly How will you keep up with the changes? Information sources Professional societies Publishers and their Web sites Vendors, manufacturers, and their web sites ©2016. Cengage Learning. All rights reserved.

Professional Societies Association for Information Technology Professionals (AITP) Targeted to IS managers and developers Local chapters Association for Computing Machinery (ACM) Targeted to computer science professionals and academicians Publications ACM Computing Surveys Communications of the ACM Institute for Electrical and Electronics Engineers (IEEE) Computer Society Targeted to computer engineers Computer Spectrum ©2016. Cengage Learning. All rights reserved.

Professional Societies - Continued Limitations of professional society publications A strong academic and R&D emphasis that tends to look at the future rather than the present and target readers who possess advanced specialized degree Little or no focus on specific products and technology suites that professionals might purchase or adopt Limited content and emphasis on current news items of interest to IS professionals ©2016. Cengage Learning. All rights reserved.

Technology Publishers See textbook Chapter 1 for names and links Caveats Most earn revenue in one/all of the following ways: Advertising Direct sales of goods and services Commissions on sales by advertisers and partners All three create bias – possibly manifested as: Ordering of content, links, or search results favoring organizations that have paid a fee to the Web site owner RSS and Twitter newsfeeds emphasizing organizations that have paid a fee to the Web site owner Omitting information from organizations that haven’t paid a fee to the search provider Omitting information that’s against the interests of organizations that have paid a fee to the search provider Balance source types to provide a complete picture ©2016. Cengage Learning. All rights reserved.

Vendors and Manufacturers The good Detailed product info Sometimes useful/detailed information on underlying technology The bad They’re in business to sell you goods and services, not unbiased information Beware of linked reviews – typically biased Beware of white papers – biased content masquerading as unbiased information or research ©2016. Cengage Learning. All rights reserved.

Summary Technical knowledge of computers Required to develop information systems Required to manage an organization’s information systems and infrastructure (compatibility, future trends) Must be constantly updated Self-study and training Information available on Web ©2016. Cengage Learning. All rights reserved.