ITEC100- 18 Thurs 5 pm Class
Creating a Chapter 5 Study Outline
1 Fundamentals of Telecommunications
Communications – the transmission of a signal from a sender to a receiver by way of a medium such as wires or radio waves.
Communications Medium – anything that carries a signal between a sender & receiver
1.1 Telecommunications and Data Communications
Telecommunications -- refers to the electronic transmission of signals for communications.
Examples: Some telecommunications devices that we interact with on a daily basis include telephones, radios, TVs, and computers.
Data communications -- a specialized subset of telecommunications, refers to the electronic collection, processing, and distribution of data, typically between computer systems
Telecommunications network -- connects communications and computing devices
Computer network -- a specific type of telecommunications network that connects computers and computer systems for data communications
This chapter discusses the following components of telecommunications:
¨ Networking media: Anything that carries an electronic signal and creates an interface between a sending device and a receiving device.¨ Networking hardware devices and networking software: Work together to enable and control communications signals between communications and computer devices.
1.2 Characteristics of Telecommunications
· The characteristics of telecommunications components should be analyzed in terms of speed, quality, and convenience.
· Telecommunications can allow people to be more productive.
· For example, being able to access and respond to e-mail during an hour-long daily commute on the bus or train frees up an hour later in the day for going to the gym or some other productive activity.
1.2.1 Types of Signals
If we measured the voltage on a telephone wire during a conversation, we would see something like Figure 5.4a. Notice that the figure shows a signal that continuously changes over time. This type of continuous fluctuation between high and low voltage is called an analog signal.
In contrast, if we measured the voltage on cables used to connect PCs, we would probably see something comparable to Figure 5.3b. The signal in Figure 5.3b at any given time is either high or low. This type of discrete voltage state (either high or low) is called a digital signal. The two states are used to represent the state of a bit, high for 1, and low for 0.
1.2.2 Transmission Capacities
Signal Frequency -- speed at which an electronic communications signal can change from high to low is called the signal frequency
· A faster frequency means a faster data transmission rate. Signal frequency is measured in hertz (Hz), or cycles per second.
· In computer networks, the data transmission rate is also referred to as the bandwidth and is measured in bits per second (bps).
· Today’s bandwidth options fall into one of two categories: narrowband or broadband.
Bandwidth Options¨ Broadband: Media advertised by Internet service providers as “high-speed.”
¨ Narrowband: Any medium with a speed less than 200 Kbps, typically the speeds delivered by a 56 Kbps dial-up modem connection.
TEAM NAME___ NO NAMES -- ______
Brandi Jones, Josh Hughes, Sam Kelly, James Mccune, Nick Cox
2 Networking Media, Devices, and Software
· Telecommunications network support voice others support data but still others support both voice and data.
· No matter what the type the communications that take place on these networks require networking media, hardware and software.
2.1 Networking Media
· In developing a network the selection of media depends on the environment and use of the network.
· Media should support the needs of network users.
· Depending on the environment wired networks are more secure than wireless networks which is why a government agency would choose to use a wired network over a wireless network.
· Different communications media connect systems in different ways. Some media send signals along physical connections like cables, others send signals through the air by light and radio waves.
http://store.apple.com/1-800-MY-APPLE/WebObjects/AppleStore.woa/wa/RSLID?mco=E1BD7358&fnode=home/shop_mac/mac_accessories/airport_wireless&nplm=MB053LL/A
o used for wireless internet through household. Can be used for both professional and personal use.
2.1.1 Physical Cables
2.1.1.1 Type of Cables
· Twisted pair cable- consists of pairs of twisted wires covered with an insulating layer. Ex. Type of cable that brings telephone service to your home, and is used for dial up modem connections.
· Coaxial cable- consists of an inner conductor wire surrounded by insulation a conductive shield and a cover. Ex. At one time it was preferred cable for computer networks. Now mostly used for cable televisions and radio networks.
· Fiber-optic cable- consists of thousands of extremely thin strands of glass or plastic bound together in sheathing transmits signals with light beams.
o Speed- fiber-optic cables support data transfer rates 1.6 terabits per second.
o Size- is much smaller in a diameter than many copper wires. More strands can be bundled together in smaller cables than with copper.
o Security- Copper wires are easy to tap, but the same is not true for fiber-optic cable.
o Clarity- fiber optic cables do not allow signals to bleed to one strand or another, unlike copper wire that often suffer from such interference.
http://www.bestbuy.com/site/olspage.jsp?skuId=6998047&type=product&id=1099391709909
o High-speed, error-free transfers of large files from digital cameras and other peripherals at up to 400 Mbps & 24K gold-plated and corrosion-proof connectors for maximum conductivity and durability
2.1.2 Radio Signals And Light
· Telecommunications signals can travel through air using radio waves and light.
o Radio wave- electromagnetic wave transmitted through an antenna at different frequencies.
o Ex. Fm radio, cell phones, baby monitors, and garage door openers all operate at different frequencies.
o Above microwaves in the radio spectrum comes infrared light and then visible light.
o Microwaves- waves sent at the high end of the radio spectrum, between 1 & 300 GHz.
TEAM NAME______
Members Present / Roles ______
2.2 Networking Devices
2.2.1 Modem
2.2.2 Network Adapters
2.2.3 Network Control Devices
Hubs:.
Switches:
Repeaters:
Bridges:
Gateway:
Routers:
Wireless access point:
Firewall:
TEAM NAME______
Members Present / Roles ______
3 Wireless Telecommunications Technologies
3.1 Cell Phone Technologies
3.2 Pages
3.3 Global Positioning Systems
3.4 Wireless Fidelity and WiMax
TEAM NAME______
Members Present / Roles ______
Wireless Telecommunications Technologies (continued)
3.5 Bluetooth
3.6 Infrared Transmission
3.7 Radio Frequency Identification
4 Networks and Distributed Computing
4.1 Computer Networking Concepts
4.1.1 Distributed Computing
TEAM NAME______
Brice Earnhardt- leader,Kristen Boyd- text researcher,Ryan Smith- Presenter,Aaron Rose- web searcher,Jamie Lees- typer, submitter
4.2 Network Types
4.2 Network Types
· Network-classified by size in terms of the number
4.2.1 Personal Area Network (PAN)
· Personal Area Network – the interconnection of personal information technology devices, typically wireless, within the range of an individual (typically around 33ft to 10m)
4.2.2 Local Area Network (LAN)
· LAN- network that connects computer systems and devices within the same building or local geographical area
· Virtual Private Network (VPN) an internet extended beyond the confines of the private network
1. Example: wal- mart provides key supporters with acess to its internet so that they can see what products
· Intranet-uses protocols of the internet and the web- TC/IP and http along wit internet services such as web browsers-withing the confines of a private network
4.2.3 Metropolitan Area Network (MAN)
· MAN- connects networks within a city or metropolitan size area into a larger high speed network
4.2.4 Wide Area Network (WAN)
· Wide Area Networks connect LAN’s and MAN’s between cities, across country, and around the world using microwave and satellite transmissions or telephone lines.
1. Example: college may maintain a LAN that covers the campus
4.2.5 Global Networks
· Global Networks are a wide area network (WAN) that crosses an international border.
1. Example: the popular file sharing service, kazaa, has been able to escape prosecution because it maintains its servers in Denmark, has its domain in Australia, and runs its software from the South Pacific
· URL- www.corp.att.com/globalnetworking/
Site name- AT&T global networking
Why its relevant-AT&T is a global networking service. It provides business success to Europe, Africa, Asia, and more