lecture 6 mgmt 6180 - © 2012 houman younessi understanding the technological infrastructure (part...
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Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Understanding the Technological Infrastructure (Part 1)
“Understanding Information TECHNOLOGY”(Part 1)
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Application:Collection of programs that together achieve a particular objective directly related to a task that the user wishes to perform.
Program:
Code written - in a human understandable language - that is to be executed in computer memory where it can perform tasks on data.
Algorithms + Data Structures
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Algorithm:
A finite set of well-defined instructions for accomplishing a given task which, given an initial state, will terminate in a defined end-state representing a particular goal.
e.g. A recipe to cook lasagna
e.g. A set of instructions to minimize a path traveled
e.g. A set of instructions to sort a set of numbers
Recursive, iterative; Deterministic, Non-deterministic; Serial, Parallel
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Examples of Algorithms:
Recursive Iterative
function fib(n)
if n = 0
return 0
if n = 1
return 1
else
return fib(n-1) + fib(n-2)
function fib(n)
a, c = 0 ,b = 1
Do (n times)
{ c = a+b
a = b
b = c
return b}
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MGMT 6180 - © 2012 Houman Younessi
Programming Language:Artificial Language created to produce artifacts called programs that control the behavior of automata, usually a computer.
Compilers, Interpreters;
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Example Programs in Various Languages:
int fib(int n) {
if (n <= 2) return 1
else return fib(n-1) + fib(n-2) }
(+ (fib(- N 1)) (fib(- N 2)))))
fib1,fib2 :=1
to n do begin
fib1,fib2 :=fib2,fib1; fib1 :=fib1+fib2
end;
C family
Lisp family
Algol family
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Data Structure:
A well-defined form of storing data.
• Influences the efficiency of algorithm used.
• Abstract (Data-type), Concrete (Implementation);
• Simple, Composite;
Implemented in Memory
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Example Data Structure: Stack
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MGMT 6180 - © 2012 Houman Younessi
Database:A system that provides organized collection, retention and presentation of data according to a well-defined model that ensures user selected persistence.
• Definition and query schemas,
• Models (Hierarchical, networked, relational, object)
• Transaction
• Concurrency
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Application Types:
- Compiler
- Operating System
- DBMS
- Accounting and financial management
- Inventory management
- CAD
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MGMT 6180 - © 2012 Houman Younessi
Islands of Information/Automation
Need for inter-communication
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MGMT 6180 - © 2012 Houman Younessi
Network:A collection of links arranged so that messages may be passed from one part to another usually over multiple links.
Data Communication Networks
Tele-Communication Networks
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MGMT 6180 - © 2012 Houman Younessi
Network ProtocolsThe Open Systems Interconnection Reference Model (OSI Model or OSI Reference Model for short) is a layered, abstract description for communications and computer network protocol design.
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Layer 1: Physical Layer
Defines all the electrical and physical specifications for devices including layout of pins, voltages, and cable specifications. Hubs, repeaters, network adapters and Host Bus Adapters (HBAs used in Storage Area Networks) are physical-layer devices. Ethernet incorporates both this layer and the data-link layer (Layer 2). The same applies to other local-area networks, such as Token ring, FDDI, and IEEE 802.11.The major functions and services performed by the physical layer are:
• Establish/terminate a connection• Contention resolution and flow control• Modulation, or conversion between the representation of digital data in user equipment and the corresponding signals transmitted over a communications channel. These are signals operating over the physical cabling—copper and fiber optic, for example—or over a radio link.
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Transfers data between network entities and to detect and possibly correct errors that may occur in the Physical Layer. The addressing scheme is physical which means that the addresses are hard-coded into the network cards at the time of manufacture. The addressing scheme is flat.
Examples are Ethernet, HDLC and ADCCP for point-to-point or packet-switched networks and Aloha for local area networks. On IEEE 802 local area networks, and some non-IEEE 802 networks such as FDDI, this layer may be split into a Media Access Control (MAC) layer and the IEEE 802.2 Logical Link Control (LLC) layer.
This is the layer at which the bridges and switches operate. Connectivity is provided only among locally attached network nodes.
Layer 2: Data Link Layer
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Layer 3: Network Layer
Provides the functional and procedural means of transferring variable length data sequences from a source to a destination via one or more networks while maintaining the quality of service requested by the Transport Layer. The Network layer performs network routing, flow control, segmentation/de-segmentation, and error control functions. Routers operate at this layer—sending data throughout the extended network and making the Internet possible (there also exist layer 3 (or IP) switches). This is a logical addressing scheme – values are chosen by the network engineer. The addressing scheme is hierarchical. The best known example of a layer 3 protocol is the Internet Protocol (IP).
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Layer 4: Transport Layer
Provides transparent transfer of data between end users, thus relieving the upper layers from any concern while providing reliable and cost-effective data transfer. The transport layer controls the reliability of a given link. Some protocols are state and connection oriented. This means that the transport layer can keep track of the packets and retransmit those that fail. The best known example of a layer 4 protocol is the Transmission Control Protocol (TCP). It is the layer that converts messages into TCP, User Datagram Protocol (UDP), Stream Control Transmission Protocol (SCTP), etc. packets.
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Layer 5: Session Layer
Controls the dialogues (sessions) between computers. It establishes, manages and terminates the connections between the local and remote application. It provides for either duplex or half-duplex operation and establishes check-pointing, adjournment, termination, and restart procedures. The OSI model made this layer responsible for "graceful close" of sessions, which is a property of TCP, and also for session check-pointing and recovery, which is not usually used in the Internet protocol suite.
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Layer 6: Presentation Layer
Transforms data to provide a standard interface for the Application layer. MIME encoding, data compression, data encryption and similar manipulation of the presentation is done at this layer to present the data as a service or protocol developer sees fit. Examples: converting an EBCDIC-coded text file to an ASCII-coded file, or serializing objects and other data structures into and out of XML.
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Layer 7: Application Layer
Provides a means for the user to access information on the network through an application. This layer is the main interface for the user(s) to interact with the application and therefore the network. Some examples of application layer protocols include Telnet, File Transfer Protocol (FTP), Simple Mail Transfer Protocol (SMTP) and Hypertext Transfer Protocol (HTTP).
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Towards a Real-time Infra-structure:
Better Data – Better Decisions
Improved Process Visibility
Improved Process Efficiency
Sense-and-respond (respond to actual demand rather than forecasted demand)
But for this to take place, we need to integrate more than just the production.
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MGMT 6180 - © 2012 Houman Younessi
Integration Requires:
Communication
and
Coordination
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MGMT 6180 - © 2012 Houman Younessi
Heterogeneity
- Conceptual
- Linguistic
- Technological
Volume
Access
Challenges to Information Based Integration
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MGMT 6180 - © 2012 Houman Younessi
Heterogeneity
Solutions:
- Monolithic Business Application Framework
- Open Standards/Architecture
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MGMT 6180 - © 2012 Houman Younessi
Enterprise Resource Planning Systems
ERP systems integrate information systems requirements of an organization. ERP systems usually use a single, unified database as the backbone to store data for the various system modules.
Manufacturing: Engineering, Bills of Material, Scheduling, Capacity Planning, Workflow Management, Quality Control, Cost Management, Manufacturing Process, Manufacturing Projects, Flow Optimization, Forecasting
Supply Chain Management: Inventory, Order Entry, Purchasing, Product Configuration, Supply Chain Planning, Supplier Scheduling
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Financials: General Ledger, Cash Management, Accounts Payable, Accounts Receivable, Fixed Assets Projects: Costing, Billing, Time and Expense, Activity Management Human Resources: Resources, Payroll, Training, Time & Attendance, Benefits Customer Relationship Management: Sales and Marketing, Commissions, Service, Customer Contact and Call Center support
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Advantages:
Enables Integrated design (Process efficiency)
Integration from customer requirement through to need fulfillment
Full revenue cycle management
Integrated and context based logistics management
Integrated accounting and control
Relatively secure
One “language”, One system, One vendor
Potential for:
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Disadvantages:
Expensive to acquire – Cost structures sometimes unrelated to business size.
Difficult to properly fit into the needs/philosophy of the organization. Limited and difficult customization.
Re-engineering of business processes to fit the “philosophy" (Usually a discrete manufacturing view of the world) prescribed by the ERP system may lead to a loss of competitive advantage.
Difficult/Complex to implement
As good as the weakest link
Lock-in issues. Once committed to a technology/vendor, almost impossible to switch
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MGMT 6180 - © 2012 Houman Younessi
Disadvantages:By blurring lines of responsibility, can cause problems with accountability, efficiency, and transparency.
Off-the-rack suit, may or may not fit your body, your style, or your budget
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Some ERP Providers and Products
SAP AG: World’s third largest software company headquartered in Walldorf Germany. Almost exclusively specializes in ERP solutions.
Products:
SAP R/3
mySAP All-in-one
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MGMT 6180 - © 2012 Houman Younessi
Some ERP Providers and Products
Oracle Corporation: World’s leading vendor of database management systems. Also develops and sells ERP and associated systems that rely heavily on database technologies.
Products:
Peoplesoft
Oracle e-Business Suite
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Some ERP Providers and Products
Microsoft Corporation: World’s largest software manufacturer with a wide array of products including ERP.
Product:
Microsoft Dynamics
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MGMT 6180 - © 2012 Houman Younessi
Some ERP Providers and Products
Some other providers:
SSA ERP LN by SSA Global Technologies
NetERP by NetSuite Inc.
Sage MAS 500 – by The Sage Group
SYSPRO by Syspro Inc.
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MGMT 6180 - © 2012 Houman Younessi
Examples:
Hospital
Auto-manufacturer
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MGMT 6180 - © 2012 Houman Younessi
Some Technical Issues with ERPProblems of Integration with legacy systems
Problems of fit and integration into existing business processes
Unit rather than service orientation
Not all components of a single ERP package are at the same level of utility
Difficult to integrate with supplier systems if not the same ERP
An open-architecture service-oriented solution is needed
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Open-ArchitectureOpen architecture refers to use of open-standard hardware and software to construct information systems. Open standard refers to products that are constructed using protocols and interfaces that are non-proprietary and according to a publicly available and widely adopted definition.
An architecture that enables the creation of information systems that are built by combining loosely coupled and interoperable components
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Service-Oriented Architecture
A style of potentially multi-tier computing that helps share logic and data among multiple applications and usage modes. These usage modes are defined or expressed as “services” and are aligned with the requirements of system users.
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
(Open) Service-Oriented Architecture
Essential Principles:
Interoperability
Modularity Granularity
Componentization
Reuse
Service identification
Service Categorization
Compliance to standards (both de facto and actual)
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MGMT 6180 - © 2012 Houman Younessi
Encapsulated Loosely Coupled
Contract-based
Abstract Autonomous
State-less
Composible (Granular)
(Open) Service-Oriented Architecture
Architectural Principles:
Services are:
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Advantages
1. Macro (service) level Reuse
2. Possible legacy system integration
3. Third party systems (e.g. suppliers) integration
4. Does not lock-in the user
5. Cost of acquisition
6. Tailorable (the user chooses the best product for the service)
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Disadvantages
1. Needs know-how and coordination to install and integrate
2. Lots of tailoring effort required
3. Support issues – Passing the buck
4. Tuning issues – Efficiency (component architecture mismatch)
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MGMT 6180 - © 2012 Houman Younessi
Volume
Data Storage
Data Transfer
Data Manipulation
Development
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MGMT 6180 - © 2012 Houman Younessi
Kilobyte (KB) 210 103 Three pages typical manuscript
Megabyte (MB) 220 106 War and Peace
Gigabyte (GB) 230 109 A small library (1000 books)
Terabyte (TB) 240 1012 A major university library
Petabyte (PB) 250 1015 All books ever written in the world
Exabyte (EB) 260 1018 All written words ever
Zettabyte (ZB) 270 1021 ?
Data Storage/Transfer
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
iPod 10 MB per minute
SETI 1.8 GB per minute
Internet 1.5 TB per minute
Next time your bank say that they hold and manage over 2 terabytes of data, ….. Have respect
Data Storage/Transfer
Lecture 6
MGMT 6180 - © 2012 Houman Younessi
Typical lap-top hard-disk 40-100 Gigabytes
National Bank Database 1-2 Terabytes
All databases in NYC 3-5 Pentabytes
All data in electronic form 5 Exabytes
Domestic Cable BB ~200 KB per second
Wi-Fi network ~1.4 – 2.5 MB per second
T3 ~5 MB per second
OC3 ~20 MB per second
OC768 ~5 GB per second
Intercontinental FO trunk ~50-100 GB per second
Data Storage/Transfer
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MGMT 6180 - © 2012 Houman Younessi
Data Manipulation
Moving from database querying to :
- Data mining
- Graphical data (e.g. Geographical)
- Voice data
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MGMT 6180 - © 2012 Houman Younessi
Development
Volume of work!!!
Despite common belief there is a severe shortage of SE/IS/IT staff world-wide.
- Open-sourcing
- Out-sourcing
- Off-shoring
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MGMT 6180 - © 2012 Houman Younessi
Access
Availability
Security
- Data
- Communication
- Service
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MGMT 6180 - © 2012 Houman Younessi
EXERCISE:
What ERP components would you implement and why?