© 2004 Ken Baldauf, All rights reserved. Telecom & Networks Fundamentals Telecom Components Computer Networks Network Applications Please turn your cell.

© 2004 Ken Baldauf, All rights reserved.

Telecom & Networks

Fundamentals Telecom Components Computer Networks Network Applications

Please turn your cell phone off.


Fundamentals of Telecommunications


Telecommunications

Telecommunications: The electronic transmission of signals over a medium for communications.


Types of Signals

Analog Signal: transmit sound using continuously varying levels of voltage.

Digital Signal: transmits data using two discrete states of voltage: high and low


Signal Frequency

Frequency: the speed at which a signal changes from high to low.

Bandwidth: the range of signal frequencies that can be sent over a given medium at the same time. Often expressed as bits per second Broadband: faster than 200Kbps


Review: Fundamentals


Network Media, Devices, and Software

The fundamental components of telecommunications networks

8


Networking Media

Coaxial Cable

Fiber Optic Cable

Twisted Pair Cable

Radio Waves


Radio Waves

Radio waves use differing frequencies to carry many types of information: AM & FM Radio Short Wave & CB Radio Television Broadcasts Garage Doors Openers Baby Monitors Cordless Phones Cell Phones Radio Controlled Cars and Airplanes Global Positioning Systems Wireless Computer Networks Microwave Communications

http://www.fcc.gov/oet/spectrum/ http://www.nrpb.org/understand/radiowaves/radiowaves.htm http://electronics.howstuffworks.com/radio-spectrum1.htm

10


High-frequency radio signals sent up to 30 miles through the air.

Microwave Communications

11


Microwave Communications

Line-of-sight communications

!

12


Microwave CommunicationsSatelliteTransmission

Line-of-sight required


Global Positioning System (GPS)

GPS: uses satellites to pinpoint the location of receivers on earth.

Aircraft Navigation


GPS


Seacraft Autopilot


GPS


Automobile Navigation


GPS

GPS: uses satellites to pinpoint the location of receivers on earth. Computing


GPS

GPS: uses satellites to pinpoint the location of receivers on earth. Handheld Navigation


GPS


Child Safety


GPS


Emergency Call


GPS


Auto-emergency Call


Wireless Fidelity (Wi-Fi)

Wi-Fi: devices that communicate wirelessly using the 802.11 protocol.

AccessPoint

• 250-1,000 ft range

• 802.11b 4.5 Mbps

• 802.11g 11 Mbps

• www.boingo.com

• http://talgov.com/citytlh/utilities/ubcs/canopy.html


Bluetooth Bluetooth: Wireless technology

that enables a wide variety of digital devices to communicate directly.

• 33 ft range

• 1 Mbps

• www.bluetooth.com


Infrared (IRDA)

Infrared technology utilizes infrared rays to send data over a short distance wirelessly.

• 4 ft range

• Narrow-angle cone (30o)

• Line-of-sight

• 4-16 Mbps

• www.mzoop.com


Wireless Comparison

Wi-fi Access point centered LAN

Omni-direction

Through obstructions

250 ft range indoors

11 Mbps

Bluetooth Point-to-point

Omni-direction

Through obstructions

33 ft 1 Mbps

Infrared Point-to-point

Narrow-angle

Line-of-sight 4 ft 4 Mbps


Networking Devices

Modem: modulates and demodulates signals from one form to another.

Network Adapter: Expansion card, or external device installed on a computing device used to connect to a network.


Networking Devices

Network Control Devices: Hub/Switch

Controls flow of data between devices on a network

Router Routs packets to destinations and

connects one network to another

Wireless Access Point Allows devices to connect

wirelessly to a wired network


Radio Frequency Identification (RFID)

RFID Device: tiny microprocessor combined with antenna able to store and broadcast identifying information to an RFID reader.

Currently on hold until security issues are addressed.

http://www.technologyreview.com/articles/visualize0304.asp?trk=nl


Review: Telecom Components


Networks and Distributed Computing


Networking Software

Network Operating System (NOS) system software that controls the communications

between computer systems and devices on a network. Protocols

an agreed-upon format for transferring data between devices.

Standard an agreed-upon way of doing something within an

industry. Ethernet

the most widely used network standard for private networks.


Computer Network Concepts

Distributed Computing Refers to a computing environment that

includes multiple remote computers that work together to solve problems and provide services. Database Servers Application Servers File Servers Print Servers


Types of Computer Networks


Local Area Network (LAN)

Local Area Network (LAN) Connects computer systems and devices

within a common geographic area


System Administrator

Local Area Network

Startopology

Bustopology

Servers

Wirelessaccess point

switch


router

router

Wide Area NetworkConnects LANs between cities, cross country, and around the world using microwave and satellite transmission or telephone lines.

FSU Tallahassee LAN

FSU Panama City LAN

WAN


Global Area Network (GAN)

Global Area Network (GAN) An International network


Personal Area Network (PAN)

Personal Area Network (PAN) The wireless interconnection of

personal information technology devices within the range of an individual.

Mostly associated with Bluetooth technology

http://www.scottevest.com/v3_product_info/features.shtml


Network Technologies

Intranet A private network that utilizes Internet

and Web protocols and software. Virtual Private Network (VPN)

Uses the Internet to connect an organization’s networks dispersed around the world into one large intranet.


PAN – Alternative Definition

Personal Area Network (PAN) The human body is used to conduct a minimal

electric current to transfer information from one individual to another.

The original PAN was designed by Thomas Zimmerman and allowed users to pass digital electronic information through touch, by transferring information from one person’s device to another’s, running a subtle current through the body.

http://www.almaden.ibm.com/cs/user/pan/pan.html


Exchange emails through handshake

TWO Japanese telecoms giants have developed technology that turns the human body into a broadband-paced link that allows e-mail addresses to be exchanged through a simple handshake, a report said Monday.The technology, developed by Nippon Telegraph and Telephone Corp. and its subsidiary NTT DoCoMo Inc., uses the body's conductivity and adds the smarts of a personal digital assistant (PDA), the Nihon Keizai Shimbun said. A device attached to a PDA can send and receive weak electrical signals through people, with human bodies as communications circuits, the paper said, citing sources close to the companies. Apparel and handbags have their own conductivity, allowing an electrical connection to a PDA that can remain in one's pocket, the paper said. In this way, people can exchange e-mail addresses, names and phone numbers while shaking hands, with the data automatically written into both their PDAs, the paper said. The companies have confirmed in an experiment that data can be transmitted at 10 megabits per second, comparable to the speed of a broadband Internet connection, it said. The technology could allow data communications through door knobs, switches, desks and chairs, the paper said. It could pave the way to one day being able to pass through railway ticket gates or entering secure buildings with a simple touch. It could also get a computer to start up with the proper settings as soon as the user sat down, the paper said. Agence France-Presse

See also “Microsoft patents body power”


Review: Networks


Setting Up a Wireless Home Network


Installing Home Wi-fi

Requirements High-speed Internet Cable Modem or DSL

Modem (provided be ISP)

Wireless Access Point/Router

Wireless adapters for each device.

Additional Access Points as needed. Cable Modem

Wireless Access Point / Router

To Cable Co.

http://www.linksys.com/


Cable Modem


To Cable Co.

Dangers of Home Wi-fi

Neighbors Hackers

Cable Modem


To Cable Co.



Neighbors Hackers Passer byes

www.wardriving.com

Cable Modem


To Cable Co.



War Driving Kit


Securing Home Wi-fi

Change the default SSID (network name).

Change the default password needed to access a wireless device.

Enable MAC address filtering.

Disable the SSID broadcast option.

Enable WEP or WPA encryption

Install Firewall SoftwareCable Modem


To Cable Co.


Review: Wi-fi


Questions?

Don’t forget to turn your phone back on!!

© 2004 Ken Baldauf, All rights reserved. Telecom & Networks Fundamentals Telecom Components Computer Networks Network Applications Please turn your cell.

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