It infrastructure

NETWORKS, TELECOMMUNICATIONS, AND MOBILE TECHNOLOGY Business Driven Information Systems 2e

NETWORK BASICS
Telecommunication system - enables the transmission of data over public or private networks
Network - a communications, data exchange, and resource-sharing system created by linking two or more computers, and by establishing standards, or protocols, so that they can work together

NETWORK BASICS
Three types of networks include LAN, WAN, MAN:
Local area network (LAN) - A computer network that uses cables or wireless signals to link two or more computers within a geographically limited area, generally one building or a group of buildings
Wide area network (WAN )- A computer network that provides data communication services for business in geographically dispersed areas (such as across a country or around the world). The Internet is a WAN that spans the world.

NETWORK BASICS
Metropolitan area network (MAN) - a computer network that provides connectivity in a geographic area or region larger than that covered by a local area network, but smaller than the area covered by a wide area network, usually spanning a city
May be used to link community services such as police, fire, hospitals, EMS, traffic control, broadcast systems, etc.

NETWORK BASICS

NETWORK BASICS
Networks are differentiated by the following:
Architecture: peer-to-peer, client/server
Network Operating System
Packet switching
Routers
Topology: bus, star, ring, hybrid, wireless
Protocols: Ethernet, Transmission Control Protocol/Internet Protocol (TCP/IP)
Media:
Wired: coaxial, twisted-pair, fiber-optic
Wireless: microwave, satellite, Wi-Fi, infra-red, etc.

ARCHITECTURE
Two primary types of architectures
Peer-to-peer (P2P) network
Client/server network

Architecture: Peer-to-Peer Networks
Peer-to-peer (P2P) network - a network without a central file server, in which all computers in the network have access to the public files located on all other workstations

Architecture: Client/Server Networks
Client/server network – a network in which the bulk of the back-end processing takes place on a server , while the front-end processing is handled by the clients
Client - a computer that is designed to request information from a server
Server - a computer that is dedicated to providing information in response to external requests

Network Operating System
Network operating system (NOS) - the operating system that runs a network, steering information between computers and managing security and users
Coordinates:
User accounts
Accessing information
Security
Resource sharing
Examples:
Novell NetWare; Microsoft Windows Server; Converging Technologies LANtastic

Packet-switching
Packet-switching - occurs when the sending computer divides a message into a number of efficiently sized units called packets, each of which contains the address of the destination computer
Allows millions of users to send large and small chunks of data across the Internet concurrently
Based on the concept of turn taking ; packets from each user are alternated in the shared network

Routers
Router - an intelligent connecting device (HW) that examines each packet of data it receives and then decides which way to send (route) it onward toward its destination

TOPOLOGY
Network topology - refers to the geometric arrangement of the actual physical organization of the computers and other network devices) in a network
Star
Bus
Ring
Hybrid
Wireless

All devices are directly connected to the central hub or switch
If the central device goes down, the entire network is disabled
Bottlenecks can occur since all messages must pass through the central device
Easy to manage & expand
Star Network Topology The network is configured in the shape of a star with all nodes or workstations connected to a central hub, through which all messages pass

Computers & devices are connected to a central line or cable
Each device can communicate directly with all other devices
Easy to add on to, but need to be careful about how many devices you add
Bus Network Topology The network is configured in the shape of an open-ended line with all nodes or workstations connected to the bus individually.

Computers & devices are connected in a ring; a closed circuit
Messages travel around the ring in one direction
Better traffic mgmt. & error control than bus
Less signal loss
High bandwidth
Long distances
Relatively expensive
Ring Network Topology The network is configured in the shape of a circle with each node connecting to the next node. Messages travel around the circle in one direction. Each node examines the message and uses it or regenerates it and passes it to the next node

Hybrid Network Topology
Combination of other network types
More flexible, able to accommodate specific needs in a network

Wireless Networks
Devices are connected by a receiver/transmitter to a special network interface card (NIC) that transmits signals wirelessly between a computer and a server, all within an acceptable transmission range

Review - TOPOLOGIES

PROTOCOLS
Interoperability - the capability of two or more computer systems to share data and resources, even though they are made by different manufacturers
Protocol – a standard that specifies the format of data as well as the rules to be followed during transmission – controls communication across a network

Protocols: Ethernet
Ethernet - a physical and data layer technology for LAN networking

Transmission Control Protocol/ Internet Protocol
Transmission Control Protocol/Internet Protocol (TCP/IP) - provides the technical foundation for the public Internet as well as for large numbers of private networks

TCP – Transmission Control Protocol
Breaks information into small chunks called data packets
Manages the transfer of the packets from computer to computer
Reassembles data packets back into the message at the destination
IP – Internet Protocol
Controls how data packets are formed
Addresses each packet with the source and destination address

TCP/IP applications
File transfer protocol (FTP)
Simple mail transfer protocol (SMTP)
Telnet
Hypertext transfer protocol (HTTP)
Simple network management Protocol (SNMP)

MEDIA
Network transmission media - refers to the various types of media used to carry the signal between computers
Wired media (guided, cabled)
Wireless media (unguided, broadcast)

Characteristics of Transmission Media
Speed – measured in bps (bits per second)
Bandwidth : the communications capacity of a communications channel; the range of frequencies available in the channel; the difference between the highest and the lowest frequencies that can be transmitted on a single medium
Broadband - refers to high-speed Internet connections transmitting data at speeds greater than 200 kilobytes per second (Kbps)

Characteristics of Transmission Media
Attenuation – this results when the power of an electrical signal weakens as it is sent over increasing distance
Electro Magnetic Interference (EMI) – interference commonly caused by fluorescent lights, weather, or other electronic signals that affect the distance a signal can travel as well as its quality

Wired Media
Wired Media – physical transmission media manufactured so that signals will be confined to a narrow path and will behave predictably
Three commonly used types include:
Twisted-pair wiring
Coaxial cable
Fiber Optic (or optical fiber)

Twisted Pair Two or more pairs of insulated copper wires twisted together; may be shielded (STP) or unshielded (UTP). It has the lowest capacity of the cable options
Advantages:
High availability
Low cost
Known technology
Disadvantages:
Slow for data
Interference (susceptible to attenuation and EMI)
Security

Coaxial Cable Contains a solid inner copper conductor surrounded by insulation and outer braided copper or foil shield . It comes in different thicknesses and is higher capacity than twisted pair
Advantages:
Greater capacity (bandwidth)
Faster
Less interference (less susceptible to attenuation & EMI)
Disadvantages:
Not as widely available as twisted pair
More expensive
Security

Fiber-Optic
Made of light-conducting glass or plastic core, surrounded by more glass , called cladding , and a tough outer sheath. It is high capacity and is mainly used in high speed backbones
Advantages:
Much greater speed and capacity (very high bandwidth)
No electrical interference (immune to EMI)
Very secure
Low attenuation
Fits into small spaces
Disadvantages:
More costly
More difficult to install and maintain

Wired Media

Wireless Media
Wireless media - natural parts of the Earth’s environment that can be used as paths to carry electrical signals; no physical transmission media
Infrared light
High frequency radio
RFID
Bluetooth
Pagers
Cellular
Wi-Fi & WiMax
Microwave/satellite transmission

Infrared light
Uses high-frequency light waves to transmit data on an unobstructed path between nodes – computers or other devices such as a printer – on a network up to 24.4 meters (i.e. most electronic remotes use this infrared light)
are susceptible to attenuation , EMI , eavesdropping , high-intensity light , and smoke

Hi Frequency Radio
A fast transmission medium for distances up to 40 kilometers, depending on obstructions. Attenuation is very low within the prescribed distance, but is susceptible to EMI and eavesdropping.
Applications of this technology include
RFID
Bluetooth
Pagers
Cellular phones
Wi-Fi/Wi-Max

RFID - Radio Frequency Identification
Radio frequency identification (RFID) - uses active or passive tags in the form of chips or smart labels that can store unique identifiers and relay this information to electronic readers
RFID tag - contains a microchip and an antenna, and typically work by transmitting a serial number via radio waves to an electronic reader, which confirms the identity of a person or object bearing the tag

Radio Frequency Identification (RFID)

Bluetooth
Bluetooth – a telecommunications industry specification that describes how mobile phones, computers, and personal digital assistants (PDAs) can be easily interconnected using a short-range wireless connection; transmits over the unlicensed 2.4 GHz frequency band

Bluetooth
BMW’s new motorcycle helmet “System-Helmet 5” can be equipped with a Bluetooth network that allows riders to operate their Bluetooth-enabled cell phones, using hands-free operation through the motorcycle’s navigation system. (not approved in USA)
http://www.bmw-motorrad-authorities.com/authorities/en/index_frameset.html?content=http://www.bmw-motorrad-authorities.com/authorities/en/equipment/riderspoint/products/systemhelmet_5.html

Pagers
A one way, wireless messaging system in multiple types

Cellular Phone A two-way wireless communication that assigns a call to a frequency, and hands it off to another cell with a different frequency as you move from area to area

Cellular Transmission

http://www.prattfamily.demon.co.uk/mikep/gsmnet.html GSM Base Station photos - One2One

USING CELLULAR TECHNOLOGIES IN BUSINESS

USING CELLULAR TECHNOLOGIES IN BUSINESS
The latest trends in cell phones reflect a convergence of voice, video and data communications
Personal digital assistants (PDA) are small, handheld computers capable of entirely digital communications transmission
Smartphone - combines the functions of a cellular phone and a PDA in a single device

WIRELESS FIDELITY (Wi-Fi)
Wi-Fi (Wireless fidelity) – based on the IEEE standard called 802.11, this technology enables multiple computers to share Internet access, files, and peripheral devices within ranges of 150’ – 300’
A, B, G, Super G, N, Xtreme N
The main problem with Wi-Fi access is that hot spots are relatively small, so coverage is limited

WIRELESS FIDELITY (WiMAX)
WiMAX (Worldwide Interoperability for Microwave Access) – based on the 802.16 standard, enables wireless networks to extend as far as 30 – 50 miles
A WiMAX system consists of two parts:
A WiMAX tower - A single WiMAX tower can provide coverage to a very large area - as big as 3,000 square miles
A WiMAX receiver - The receiver and antenna could be built into a laptop the way Wi-Fi access is today

Microwave A high frequency radio signal that is sent through the air using either terrestrial (earth-based) or satellite systems Terrestrial Microwave - A line-of-site technology (unobstructed) used to cross inaccessible terrain or to connect buildings where cable installation would be expensive. Attenuation is low over short distance but higher over longer distances. High winds , heavy rain , EMI and eavesdropping are also problems.

Satellite Microwave - A line-of-site technology that uses relay stations to transfer signals between antennae located on earth and a satellite orbiting the earth . It can be used to access very remote locations and like terrestrial microwave, attenuation , EMI and eavesdropping are also problems

Satellite Microwave

USING SATELLITE TECHNOLOGIES IN BUSINESS
Global positioning system (GPS) – a "constellation" of 24 well-spaced satellites that orbit the Earth and make it possible for people with ground receivers to pinpoint their geographic location by determining current latitude, longitude, speed, and direction of movement
Market for GPS services is at $5 billion with expectations for the demand to double over the next five years
Location accuracy is anywhere from 10 to 100 meters

Global Positioning System (GPS)

Geographic Information System (GIS) - is designed to work with information that can be shown on a map
Most location based applications use a GIS combined with database and GPS technology

Location-based services (LBS) - are wireless mobile content services which provide location-specific information to mobile users moving from location to location
Common Location Based Services based on GIS/GPS technology:
Finding what is nearby
Routing information
Information alerts
Mapping densities
Mapping quantities

GPS Shoes
http://www.youtube.com/watch?v=n5wMza29JwI

INCREASING THE SPEED OF BUSINESS – Comparing Media

INCREASING THE SPEED OF BUSINESS – Comparing Media Advantages & Disadvantages of Broadband Tech.

Using Networks and Telecommunications For Business Advantages
Network and telecommunication applications/competitive advantages include:
Voice over IP
Networking businesses
Increasing the speed of business
Securing business networks

VOICE OVER IP (VoIP)
Voice over IP (VoIP) - uses TCP/IP technology to transmit voice calls over long-distance telephone lines/Internet connections

NETWORKING BUSINESSES – Supporting E-Business
Industry-leading companies have developed Internet-based products and services to handle many aspects of customer and supplier interactions
Customers now expect seamless retailing between online and in-store

NETWORKING BUSINESSES – Supporting E-Business

SECURING BUSINESS NETWORKS
Network security is important – networks are a tempting target for mischief and fraud
Organizations are concerned about…
Authentication, Authorization, Access to and protection of data

SECURING BUSINESS NETWORKS
Virtual private network (VPN) - a way to use the public telecommunication infrastructure (e.g., Internet) to provide secure access to an organization’s network
Valued-added network (VAN) - a private network, provided by a third party, for exchanging information through a high capacity connection

BUSINESS DRIVERS FOR A MOBILE WORKFORCE
Companies worldwide are going wireless to increase productivity, speed delivery to market, and reduce operating costs
Wireless transmissions rely on radio waves, microwaves, and satellites to send data across high frequency radio ranges that later connect to wired media

BUSINESS DRIVERS FOR A MOBILE WORKFORCE
The terms mobile and wireless are often used synonymously, but actually denote two different technologies
Mobile means the technology can travel with the user, but it is not necessarily in real-time
Wireless refers to any type of electrical or electronic operation that is accomplished without the use of a “hard wired” connection

BUSINESS DRIVERS FOR WIRELESS TECHNOLOGIES
Drivers of wireless technology growth include:
Universal access to information and applications
User convenience, timeliness, and ability to conduct business/communicate 24x7
The automation of business processes
Sheer number of U.S. wireless device users

BUSINESS DRIVERS FOR WIRELESS TECHNOLOGIES
Wireless devices changing business include:
Wireless local area networks (wLAN)
Cellular phones and pagers
Cordless computer peripherals
Satellite radio and television
WiFi and WiMAX
Security sensors
Global Positioning Systems (GPS)

MOBILE WORKFORCE TRENDS
Social networking gets mobilized
Mobile TV
Multi-function devices become cheaper and more versatile
Location-based services
Mobile advertising
Wireless providers move into home entertainment
Wireless security moves to the forefront
Enterprise mobility

It infrastructure

by raptrovic on Jul 29, 2010

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It infrastructure — Presentation Transcript