The Advantages of Using Network Marketing Solutions for Student Presentations

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1 ISM 50 - Business Information Systems Lecture 12 Instructor: Magdalini Eirinaki UC Santa Cruz May 10, 2007

2 Outline Announcements Student Presentation Client-Server Computing (cont d) SUN Case (cont d) Student Presentation Modularity and Layering

3 Announcements News Folio 2 DUE on Tuesday, 5/15 Include a print/copy of the article Midterm solutions on the web (under SECURE directory) Next time read: Ch. 7 Messerchmitt

4 Sources You should cite at least 5 non-web sources Ideally a lot more! A list of sources is included in 1st lecture s slides If an article is available on-line and also in print, you should cite the print version!!!! Only cite a website if you are sure there is no print version of the material available. Your citation of the print version may also indicate a website where the same article is available. Wikipedia is a nice source for gaining some background knowledge on your research or find links to other sources BUT is not always 100% accurate/true

5 Citing Sources More than thirty words verbatim must be cited. Any facts or figures that are not your own must be cited in the body of the text!!!! Ebay s revenues in US Revenues in 2002 were $1.39 billion [1]. [1] Ebay 2005 Annual Report. Any Tables of figures must be cited!! You can create tables/charts based on your findings

6 Citing Sources STYLE 1 STYLE 2 Companies that have deployed Internet technology have been confused by distorted market signals, often of their own creation. 1 1 M. Porter, Strategy and the Internet, Harvard Business Review, March 2001, pp Footnote at page bottom Companies that have deployed Internet technology have been confused by distorted market signals, often of their own creation. [1] References: [1] M. Porter, Strategy and the Internet, Harvard Business Review, March 2001, pp Footnote indicator Citation indicator Matches reference number in References section at the end of text.

7 Business Paper Proposals Will be handed back to you on Tuesday Grades will be posted on WebCT Make sure you read the comments and use them to make your paper better.

8 Announcements Database Tutorials MSAccess Will help you on your DB Assignment that will be out soon 3 labs You should register and attend ONLY ONE To register visit class forum Sign up with your name under the day/time that you prefer First come-first served (if class is full then you will have to choose another day/time)

9 Announcements Database Tutorials Dates: 5/18 (Friday), 10:30-11:30 AM, BE 109 5/18 (Friday), 3:00-4:00 PM, Ming Ong PC (Merrill Room 103) 5/21 (Monday), 1:00-2:00 PM, Ming Ong PC (Merrill Room 103) Each student should attend ONLY ONE

10 Announcements Next week s presentations: 5/15 5/17 Andy Pun (news) Yukie Boku (news) Kel Alexander Young (business paper: EBay) Bret Constantino (business paper: Amazon.com)

11 Student Talk Molly Glossip Brave New (Virtual) Worlds & Second Life: A new world of e-commerce WWD.COM

12 Client-Server Computing (continued)

13 Three-tier client/server Application server Client Enterprise data server

14 3-tier Client/Server Architecture Many organizational applications incorporate mission-critical databases Need to separate data from the applications that access them Centralized storage Security Fault tolerance Data shared across many applications

15 3-Tier Client Server Architecture example Client Application Server Clicks, keystrokes Balance $0.50 <head> <title>bank of America Online Banking Accounts Overview</title> <meta name="description" content="bank of America Online Banking - Accounts Overview"> <link rel="stylesheet" type="text/css" href="/easdocs/images/win_ie.css"> <script language="javascript" type="text/javascript" src="/easdocs/ias_js/scripts.js"></script> <script language="javascript" type="text/javascript">  </script> $0.50 What is Bob s balance? Shared data

16 3-Tier Client Server Architecture example Client Application Server Web Server Application Logic What is Bob s Balance? Common Gateway Interchange Shared data

17 3-Tier Client Server Architecture example Client Application Server Shared data Web Server Application Logic What is Bob s Balance? Database Management System (DBMS) Database Common Gateway Interchange

18 3-Tier Client Server Architecture example Client Application Server Web Server What is Bob s Balance? Java Servlet Application Logic In some implementations Application Logic and Web Server can be put on Different machines. Shared data Database Management System (DBMS) Database

19 3-Tier Client Server Architecture in General Client -Accept instructions from user -Make requests of server -Display responses of server Application Server -Takes input from clients -Decides what to be done next -Decides what shared data to access and manipulates it -Processes shared data -Support multiple applications with common data -Protect critical data -Decouple data administration and application administration Enterprise Data

20 Scalability Need to serve multiple customers at the same time Customer base can grow large Many identical application servers Each user session carried by a single server Each server can handle a limited number of clients More than one databases Storing different kinds of data (e.g. customers, orders, products, etc.)

21 Clients Customer logic Acquirer bank Fulfillment logic Databases Customers Merchandise Orders Book distributors Slide adapted from slides for Understanding Networked Applications By David G Messerschmitt. Copyright See copyright notice

22 Two Host Architectures Client-Server Attractive for information access and organizational applications Peer-to-Peer (P2P) Appropriate for direct/immediate applications where no centralized application logic is needed

23 Peer to Peer (P2P) Client Server Server Client Peer Peer Slide adapted from slides for Understanding Networked Applications By David G Messerschmitt. Copyright See copyright notice

24 Peer to Peer (P2P) Each peer provides the same functionality A P2P Network relies on computing power bandwidth of each peer Ad-hoc connections: Each peer joins/leaves the network at any time What is P2P good for? File sharing Video Conferencing Internet telephony Etc.

25 C/S vs. P2P Types of computers: Type of network: Communication: Powerful computers used as servers. Different machines from clients. Predefined number/topology of servers. Clients can connect/leave any time. To and from the server. Each peer is both a client and a server. Ad-hoc connections. Among peers. Network relies on: Computing power/availability of a limited number of servers. Computing power/bandwidth of each peer. Most P2P applications also have a C/S part E.g Napster, IRC P2P File sharing/transfer C/S searching

26 Sun Case (continued)

27 Sun N-tier case What does Sun make? Workstations Servers Software

28 How Successful had Sun been up to 1998? Founded in 1982 Open Standards Workstation Unix Operating System (Solaris) 1988 Revenues $1 billion 1993 Market value $3.6 billon Known for its workstations (addressing engineers) 1997 Jumped from 3 rd to 1 st in Unix Server Market. Achieved a 75% year-over-year increase in total server shipments

29 How Successful had Sun been up to 1998? Last standing, fully integrated computing company * Designed its own hardware/software: SPARC microprocessor Solaris OS Networking capabilities (TCP/IP) Scalable, Reliable network computing for large corporations ERP systems Intranets (SCM, , file directories etc) * Brent Schlender, Fortune Magazine (Oct 1997)

30 How Successful had Sun been up to 1998? 1993 Sun s CEO: The network is the computer. Sun adapts Solaris OS to coordinate data on networks 1994 Internet explodes in popularity Sun is the leader in network computing

31 Java Sun introduces Java Programming Language Portable between computers with different hardware/operating system platforms JVM: Java Virtual Machine Easy to write programs in Easier re-use: Write once, run everywhere But, programs were slow Constant updates on JDK library Programmers had to update to current versions Some felt that language was not yet mature

32 Java Applets Key feature of Java Applets: chunks of Java code Usually embedded in other applications, e.g. Web Pages Initially enabled animations on web pages Later used to facilitate e-commerce applications, in cellular phones, etc. Applets are downloaded through the browser Only what and when was needed No need to keep a copy on client! Servlets One can think of them as server-side applets

33 In the meantime, Microsoft Dominated Desktop software (mid 90 s) Users familiar with Windows, Office, etc. Windows NT servers Fine for small intranets, not industrial strength

34 What problems did the micro era produce? Desktops are expensive to maintain TCO for windows PC $9900! Every PC had a lot of software that had to be maintained Office, Windows, etc Small differences, like the order in which software is installed, could make different PCs behave differently! Keep all PCs in organization updated with current/same software releases Compatibility issues

35 In the Networking Era These bloated PCs are networked and termed fat clients. But networking of PCs offered the possibility of putting most of the functionality into servers getting rid of much of the software on the client These clients would be called thin clients. Sun, Oracle, and others saw it as the future.

36 Hardware for thin clients A Network Computer (NC) a computer with minimal hardware that depends on a network connection to a server to function Trademark of ORACLE, used by ORACLE, SUN, Acron Be careful not to confuse it with the phrase networked computer! Example: Sun s JavaStation ( ) It is the hardware one would use to implement a thinclient computing model: Store desktop on the network Send desktop via browser to the client Much less unique instances of working environment

37 In the meantime... NetPC was a PC introduced by Microsoft and Intel in 1996 Same software as a normal PC Did not allow users to install their own software NetPC died out Features of it, and Microsoft s Zero Administration Kit, live on in today s version of windows.

38 What would you do If you were in the executive board of Microsoft?

39 Microsoft Vision Keep fat-client model Add some features to Windows to reduce administration costs

40 Microsoft vs. Java Announced that will embrace and extend promising technologies and emerging open standards 1996: Sun licenses Java to Microsoft to integrate into Explorer Microsoft downplays Java s importance Did not deliver compatible implementation of Java in its products Customers were frustrated since the Java-components would not work Includes Java in its programming platform BUT incorporates proprietary components making it impossible to run on different OS

41 Sun s Vision Thin Client model Application Servers with Applications written in Java Applets/Servlets NCs could retrieve applications from application server as needed Applications compatible with any NC hardware and OS Applications could be fixed, added, updated at the server level, rather than maintaining each PC

42 SUN 3 - Tier

43 Sun N-tier

44 Sun N-Tier

45 Sun s Performance TTM , , , , , , ,584.0 (1,048.0) (2,653.0) (461.0) , , (587.0) (3,429.0) (388.0) (106.0) (54.0) , , (587.0) (3,429.0) (388.0) (106.0) (0.18) (1.07) (0.12) (0.03) (0.18) (1.07) (0.12) (0.03) Net Income , , (587.0) (3,429.0) (388.0) (106.0)

46 Today 3-tier model common. Sun s version of 4-tier model not-common. N-tier model where Webserver and Application Server on separate equipment also common. Sun s hardware business not strong. Linux on cheap PCs most common servers Microsoft desktops replacing Sun workstations

47 Today Java Common in Server implementations Example: Java Servlet implementing application logic in a banking application. Often used to push simple applets onto client Not common For big desktop applications Other languages, e.g. C/C++ still faster Microsoft is still in business

48 Student Talk Kevin Bell Halo 3 Beta in May, New Video now Gamespot.com

49 Game consoles used in research Protein Folding Project at Stanford University Studies how proteins are folded/de-folded and how this affects diseases (e.g. Alzheimer s, Parkinson s, etc.) Many complex calculations that might take years to compute Sony s PS3 users can subscribe to this project and contribute some of their machine s power to this project Joined in March Made calculations much faster (reduced to weeks) Others (e.g. Microsoft s XBOX) consider following (in News yesterday)

50 Modularity and Layering

51 Application Architecture Design The most important step Hardest to change Influences everything that follows Conceptualization What is it you are trying to do? Example Concept: Small HHC for flight attendants. HHC tells flight attendants which passengers are higher priority. Who paid the highest fares Who has been a more valuable customer in past Flight attendant discriminates based on this Free drinks, meals, and pillows to valuable customers

52 Example Concept:

53 Architecture How do you begin to architect a solution for a problem like this? Break it into modules!

54 3-Tier Architecture HHC Server Wireless Link HHC HEADQUARTERS Airline Intranet Airline Dataserver Each Tier is decomposed into modules

55 HHC Architecture HHC Application Communication With HHC Server User Interface Data Management When a module is composed of sub-modules, the architecture is hierarchical.

56 HHC Architecture HHC Application Communication With HHC Server User Interface Palm OS Data management Networking Infrastructure We are using a layered architecture as well. Allows reuse of previously built infrastructure.

57 Granularity tradeoff How big should we make the modules Many simple small ones (fine granularity) Or a few complicated big ones (coarse granularity) Which is better? Coarse Granularity: Fewer things to keep track of Fine Granularity: Modules are simpler and easier to understand Hierarchy of modules: Allows the system to be viewed at different granularity levels.

58 HHC Server HHC Server Application Computation of key statistics Communication with HHC Windows OS Networking Infrastructure Communication with airline database Again, we see layering and hierarchy. Between each module we specify an interface

59 Data server DBMS Standard Database queries (SQL) from HHC Server Database Our architecture makes use of the existing interface of the airline database, so we don t need to redesign it!

60 Interface Each module interacts with the others through its interface Interface vs. Implementation The interface shows to the other modules What functions are performed by this module How to invoke these functions The actual functionality of the module is part of its implementation Different versions of a module might share the same interface, but have different implementation The other modules (or users) cannot tell the difference!

61 A simple interface: from within our HHC Server Architecure Computation of key statistics List of numbers Mean, Variance Compute Mean and Variance HHC Application Palm OS Computation of key statistics Communication with HHC Networking Infrastructure Communication with airline database

62 Interfaces N numbers of Float type Compute Mean and Variance Computation of key statistics 2 Numbers of float type that signify: Mean, Variance Interface specifications are often made precise by using data types Example type: float A number with a decimal place (Real number) Has a certain allowable range, and precision

63 More on Data types Data passing an interface is often specified in terms of a limited number of standard data types Data type = range of values and allowable manipulation Data type does not presume a specific representation, to allow heterogeneous platforms

64 Example data types Integer natural number between -32,767 and +32,768 Could be represented (in many ways) by 16 bits since 2 16 = 65,536 e.g. 15 Float number of the form m*10 n /32768, where m is in the range -32,767 to +32,768 and n is in the range -255 to +256 Could be represented by 16+8 = 24 bits E.g. π =

65 More data types Character single character from the Roman alphabet, plus digits, space, punctuation marks and special characters String could be represented by 7 or 8 bits e.g. A, 3,!, An ordered set of n characters, where n is customizable could be represented by 7*n bits e.g. Data

66 Compound data types Programmer-defined composition of basic data types Example: Employee { String name; String address; Integer year_of birth; Float salary; }