Title: Telecommunications
1Telecommunications
- Modems
- Communication Lines
- Internet Service Providers
- Agricultural Telecommunications Act
2Connecting to the Internet?
Computer
Modem
ISP
Internet
3Bits and Bytes A Refresher
- All computer data is transmitted as a series of
0s and 1s. These are called Binary Digits. - A Bit is one numeral, an 0 or a 1
- A Byte is 8 bits
- 01000001 is an A
- 00111101 is an
- A Kilobyte (K or KB) is 1000 bytes (really 1024
bytes) - A Megabyte (M or MB) is 1,000,000 bytes
- A Gigabyte (G or GB) is 1,000,000,000 bytes
4Modems Communication Lines
5Confused??
Cable Modems
ISDN
33.6 Kbps
T1 Lines
6Modem
- A device that translates the analog signals that
travel over voice phone lines to the digital
information understood by computers. - The term modem derives from modulate/demodulate
which describes the conversion process.
7Modems
- Analog Modems
- 14.4 Kbps (Kilobits per second)
- 28.8 Kbps
- 33.6 Kbps
- Analog/Digital Modems
- 56 Kbps
- X2 Technology U.S. Robotics
- Flex technology Lucent, Rockwell
- These two technologies compete and are not
compatible (similar to beta vs. vhs) - V.90 this is superior to either X2 or Flex
8Modems/Communication Lines
- ISDN (Integrated Services Digital Network) A
true digital modem - Requires a ISDN phone line (which is digital)
- Transmits data on two 64 Kbps channels which can
be combined into a 128 Kbps stream - More expensive than traditional phone lines and
modems (Internet Service Provides may charge
more) - More complicated to setup and use
- It is rapidly loosing out to newer technology it
is nearly a historical footnote now
9Modems/Communication Lines
- Cable Modems
- Rented from your cable television company
- Cable TV company serves as the Internet Service
Provider - Can achieve speeds 10X faster than ISDN lines
(1,500 Kbps) - Speed is slowed as more people get on the same
cable - Limited availability
10Modems/Communication Lines
- DSL or ADSL Digital Subscriber Line
- A system developed by the phone companies to
compete with cable companies - Digital signals are sent over existing phone
lines - The further you are away from the switching
station, the slower the connection - 25x faster than a 56 Kbps modem
11Communication Speeds
12Modems/Communication Lines
- T1 lines
- A fiber optic cable that carries voice and
computer data - It is 60X faster than a standard modem (1.544
Megabits per second) - Often used for networks
- Very reliable
- Costs 1,000 to 1,500 a month
- T3 lines
- 3X faster than a T1
13Would You Believe?
- Modems are available today that operate at
speeds up to 9600 baud. As of today, speeds
higher than 1200 baud are not common on most
networks. - Camp, Moore, Foster Moore Microcomputer
Applications for Students of Agriculture,
Interstate, 1988 - Note at low speeds a baud 1 bit
14Modem Speed Time Line
- 300 bits per second 1963 to 1983
- 1200 bps 1984
- 2400 bps
- 9600 bps 1991
- 19.2 Kbps
- 28.8 Kbps
- 33.6 Kbps
- 56 Kbps 1998
- DSL (10 Mbps) 1999
15Modems
- Internal
- Less expensive
- People dont mess with the settings
- Doesnt take up desk space
- No power cord to plug in
- External
- Easy to install if there is no existing modem
16Modem Brands
- The top two rated brands are
- U.S. Robotics
- 3Com
17Emerging Modem Trends
- Wireless Modems
- Cellular
- Satellite Modems
- Bounce signals off satellites
- 38 Mbps
18Internet Service Providers (ISPs)
19Internet Service Provider (ISP)
- ISP Short for Internet Service Provider, a
company that provides access to the Internet. For
a monthly fee, the service provider gives you a
software package, username, password and access
phone number. Equipped with a modem, you can then
log on to the Internet and browse the World Wide
Web and send and receive e-mail. - There are about 10,000 ISPs in America
20Selecting an ISP
According to readers of Inter_at_active Week
- Network Reliability
- Few busy signals
- Doesnt disconnect
- Value for the Price
- Network Performance
- Doesnt lose data
- Customer Service Responsiveness
- Technical Support
- Start up-time
- How easy is it for a novice to get connected
21Selecting an ISP
- Local Access Number
- In most medium and larger cities, there is a
local access number - In rural areas, this could be a problem
- If you must dial long distance to access an ISP,
out of state is sometimes cheaper. - Toll-free ISPs tend to charge by the minute, so
they recoup the cost - Customer Service
- If you need help setting up your service, will
help be available
22Selecting an ISP
- Size
- Sizes range from 1-2 people to giant corporations
employing thousands - 48 of ISPs serve only one area code
- 96 of ISPs serve less than 10 area codes
- Size doesnt determine quality of service but
does have an impact on access across the country
for the traveler
23ISPs
Area Codes Served
24Leading ISPs (in subscribers)
25Customer Satisfaction with ISPs
According to readers of PC Magazine
- Dial Up
- Local ISPs A-
- EarthLink B
- ATT World Link B
- NetZero C
- Juno C
- Prodigy C-
- MSN D-
- AOL E
- Broadband
- Optimum Online A
- Road Runner A-
- Local ISPs B
- Earthlink C
- Charter Pipeline C
- Bell South C
- Verizon C-
- ATT C-
- SBC D-
- Comcast D-
- AOL D-
26Web Hosting
- Many ISPs allow you to maintain a web site at no
charge. - There are several companies that provide free web
hosting service. - The bigger ones are
- Tripod
- Yahoo Geocities
27Agricultural Telecommunications Act
28Agricultural Telecommunications Act
- Authorized in Section 1673 of the Food,
Agriculture, Conservation, and Trade Act of 1990 - provides financial assistance through the USDA
for the production and delivery of educational
programs in agricultural extension, research, and
academic programs. - U.S. institutions of higher education are
eligible to receive the grants.
29Agricultural Telecommunications Act
- Objectives
- Assure that producers, processors, researchers,
and the public have immediate access to
knowledge. - Improve the competitive position of U.S.
agriculture in international markets. - Respond to food safety and environmental
concerns. - Improve the training of students for careers in
agriculture and food industries. - Identify new uses for agricultural commodities
and increase demand.
30Agricultural Telecommunications Act
- Funds administered by the American Distance
Education Consortium (ADEC) - The NC State Department of Agricultural and
Extension Education is the recipient of a 75,000
grant to develop LEAP (Licensure in Education for
Agricultural Professionals) a web-based
alternative teacher licensure program to certify
agriculture teachers.
31Future Projections
32Predictions
- Internet printing All printers will have URLs.
You can direct a job to be printed on any printer
in the world provided you know the URL.
33Predictions
- PNG Graphics The jpg and gif graphics now in
use on the internet will be replaced by png
(portable network graphics).
34Predictions
- People today walk around with their electronic
tool belts (Palm Pilot, cell phone, pager)
therefore we will soon have - PANs Personal Area Networks
- links devices for security, entertainment,
credit, medical monitoring, transportation and
data communication. - Wearable computers and communication devices
35Predictions
- In-vehicle computing and connectivity
- computers will be standard equipment on cars
- light poles will contain wireless hubs, these
wireless hubs will transmit to central
communication centers - some towns today are nearly wireless
36Predictions
- Voice User Interface
- most computing devices will respond to voice
commands
37Predictions
- Interactive Television
- most televisions will be internet ready
- there will be interactive programming
38Predictions
- Moores Law continues
- technology doubles every 18 months
39Predictions
- CPU Speed
- 12 GHz soon
- CPU Architecture
- 64 bit CPU soon (Merced Intel, Sledgehammer -
AMD)
40Predictions
- Compact FlashMemory Cards
- Zip drives and floppies will be replaced by
compact flash memory cards
41Predictions
- 120 GB hard drives will be standard by 2005