Network and Telecommunications

The evolution in telecommunication: From wire to wireless.

Telecommunication is a highly technical, rapidly changing field of information system technology. However, it is necessary that you understand some of the important characterictics of the basic components of telecommunications networks.

-Terminals:any output/input device that uses telecommunications networks to transmit or receive data.

-Telecommunication processors:data transmission and reception between terminals and computers.

-Telecommunications channels:which data transmitted and received that use combination of media.

-Computers:of all types are interconnected by telecommunication networks.

-Telecommunications control software:consists of programs that control telecommunications activities and manage the functions of telecommunications networks.

Wired Technologies

Twisted-Pair Wire-ordinary telephone wire,consisting of copper wire twised into pairs.

-used extensively in home and office telephone systems and many

local area networks and wide area networks.

-transmission speeds can range from 2 million bits per second to

100 millions bits per second.

Coaxial cable-consists of a sturdy copper or aluminum wire wrapped with spacers to

insulate and protect it.

-groups of coaxial cable may be bundled together in a big cable for ease

of installations.

-allow high-speed data transmission from 200 million to over 500 million

bits per-second.

-used in many office building and other worksides for local networks.

Fiber optics-consists of one or more hair-thin filaments of glass fiber wrapped in a

protective jackets.

-speeds is hundreds times faster than coaxial cable and thousands of times

better than twisted-pair wire lines.

-less need for repeaters for signal retransmissions than copper wire media.

Wireless technologies

Terrestrial microwave-invovles earthbound microwave systems that transmit high

speed radio signals in a line-of-sight path between relay

stations spaced approximately 30 miles apart.

-placed on top of building,towersand mountain peaks.

Communications satellites-used microwave radio as their telecommunications

medium.

-satellites are powered by solar penals and can transmit

microwave signals a rate of several hundred million bits per

second.

Cellular and PCS systems-used several radio communications technologies.Divide a

geographic areas or cells.

-each cell has its low-power transmitter to relay calls from

one cell to another .

Wireless LANs-a high-frequency radio technology similar to digital cellular called

spread spectrum.

-eg.WiFi is faster and less expensive,enable laptop PCs,PDAs,and other

devices with WiFi modems to connect easily to the internet.

Bluetooth-short range wireless technology.is rapidly being built into computers and

other devices.

-operates about 1Mbps and has an effective range from 10 to 100 meters.

Data Management

• Data Management
• is the process of managing data as a resource that is valuable to an organization or business. One of the largest organizations that deal with data management, DAMA (Data Management Association), states that data management is the process of developing data architectures, practices and procedures dealing with data and then executing these aspects on a regular basis.
• A Database Management System (DBMS)
• is a set of computer programs that controls the creation, maintenance, and the use of the database with computer as a platform or of an organization and its end users. It allows organizations to place control of organization-wide database development in the hands of database administrators (DBAs) and other specialists.
• 
  
• A DBMS
• is a system software package that helps the use of integrated collection of data records and files known as databases. It allows different user application programs to easily access the same database. DBMSs may use any of a variety of database models, such as the network model or relational model. In large systems, a DBMS allows users and other software to store and retrieve data in a structured way. Instead of having to write computer programs to extract information, user can ask simple questions in a query language.

Traditional File Processing

Traditional File-Based Approach

 Collection of applications that each define and manage their own files

 File: collection of records containing logically-related data (Pascal’s files of

records, C++’s “struct” or “class” declarations, COBOL’s Data Division)

 Tight integration between program and data (files)

– physical storage structure visible in application code (e.g., ISAM, VSAM)

– run-time performance can (and must) be programmed

Limitations of File-Based Approach

 Tendency to separate and isolate logically-related data

– subsequent data models capture more information: true DB software “knows

about” some inter-entity or inter-file relationships

 Separate files ) redundancy in defining and storing data

– wasted storage space (only a problem for large applications)

– redundant efforts to enter replicated data and maintain its consistency (seri-

ous problem)

 Program-data dependence: data definition in application program ) pro-

gram valid for only one DB with a fixed structure

 Labor intensive

– maintenance difficult (duplication, procedurality)

– inter-file links must be coded in programs

3

• 
  
• 
  
• Data Mining
• Data mining, the extraction of hidden predictive information from large databases, is a powerful new technology with great potential to help companies focus on the most important information in their data warehouses. Data mining tools predict future trends and behaviors, allowing businesses to make proactive, knowledge-driven decisions. The automated, prospective analyses offered by data mining move beyond the analyses of past events provided by retrospective tools typical of decision support systems. Data mining tools can answer business questions that traditionally were too time consuming to resolve. They scour databases for hidden patterns, finding predictive information that experts may miss because it lies outside their expectations
• 
• 
  
• Data Warehouse

• Data warehousing has quickly evolved into a unique and popular business application class. Early builders of data warehouses already consider their systems to be key components of their IT strategy and architecture. Numerous examples can be cited of highly successful data warehouses developed and deployed for businesses of all sizes and all types. Hardware and software vendors have quickly developed products and services that specifically target the data warehousing market. This paper will introduce key concepts surrounding the data warehousing systems.

• What is a data warehouse? A simple answer could be that a data warehouse is managed data situated after and outside the operational systems. A complete definition requires discussion of many key attributes of a data warehouse system. Later in Section 2, we will identify these key attributes and discuss the definition they provide for a data warehouse. Section 3 briefly reviews the activity against a data warehouse system. Initially in Section 1, however, we will take a brief tour of the traditions of managing data after it passes through the operational systems and the types of analysis generated from this historical data.

• 

Key developments in early years of data warehousing were:

1960s — General Mills and Dartmouth College, in a joint research project, develop the terms dimensions and facts.

1970s — ACNielsen and IRI provide dimensional data marts for retail sales.

• 1983 — Teradata introduces a database management system specifically designed for decision support.
• 1988 — Barry Devlin and Paul Murphy publish the article An architecture for a business and information system in IBM Systems Journal where they introduce the term "business data warehouse".
• 1990 — Red Brick Systems introduces Red Brick Warehouse, a database management system specifically for data warehousing.
• 1991 — Prism Solutions introduces Prism Warehouse Manager, software for developing a data warehouse.
• 1991 — Bill Inmon publishes the book Building the Data Warehouse.
• 1995 — The Data Warehousing Institute, a for-profit organization that promotes data warehousing, is founded.
• 1996 — Ralph Kimball publishes the book The Data Warehouse Toolkit.
• 1997 — Oracle 8, with support for star queries, is released.
• 
• 

Information System Software

What is software?

Software is the general term for various kinds of programs used to operate and manipulate computers and their peripheral devices. Software is intangible meaning it “cannot be touched” and it also can be thought of as the variable part of the computer. There are many types and categories of software.

Application software - allow end users to accomplish one or more specific (not directly computer developed related) tasks.

Under the application software there are two type of software which are general purpose application software and function-specific application software.

	General Purpose Application Software			Function-Specific Application Software
Function	-Program that perform common information processing jobs for end users. Since they significantly creates the productivity of end users, they are sometimes known as productivity packages.			-Thousand of these packages support specific application for end users.
Example	- Word processing, spreadsheet, Database management ,graphic program, web browsers, electronic mail and groupware.			- Customer relationship management, enterprise resource planning, supply chain management, web-enabled electronic commerce.
General Purpose Application Program		Function				Example
Web Browsers		- software application design to support the navigation through the point-and-click hyper-linked resources of the web.				Internet explorer, Netscape Navigator, Firefox, Opera or Mozilla.
E-mail			- software to communicate by sending and receiving messages and attachments via the internet, intranet, or extranet.		Window live hotmail, yahoo mail
Word-processing			- allow user to create, edit, and print documents and it can also convert document to HTML format.		Microsoft word, Lotus WordPro, Corel WordPerfect
Electronic Spreadsheet			-Used by business for analysis, planning and modeling. - worksheet of rows and columns. -Help you develop charts and graphic displays of spreadsheet results.		Microsoft Excel and Corel QuattroPro
Database			- software that provides tools for organizing data into a form that allows for efficient search and retrieval.
Groupware			- software that helps workgroups collaborate on group assignments. -combines a variety of software and functions to facilitate collaboration.		Lotus notes, Novell Group Wise, Microsoft Exchange

Application software for business comes in two primary forms : Custom software and Commercial Off-the-shelf(COTS).

Custom software - use to identify software applications that are developed within

an organization for used by the organization and it is owned by

the organization that developed it.

Commercial Off-the-shelf - developed with the intention of selling the software in

multiple copies to make profit. The purchasers of

COTS software generally have no control over the

specification, schedule, evolution, or access to either

the source code or internal documentation. A COTS

product is sold, leased, or licensed to the general

public but the vendor of the product retains the

intellectual property rights of the software.