Post on 23-Dec-2015
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Making Sense of Your Connectivity Options
Paul Kleeberg, M.D.American Academy of Family Physicians Scientific AssemblyOctober 3rd, 2003New Orleans
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Objectives
Understand the different methods of connecting to the Internet
Know the benefits, limitations and approximate cost of each method
Know how multiple computers can share one connection
Know how these techniques can be applied in your home or office
Know how to set up a secure wireless network in your home or office
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Outline
Connecting to the Internet POTS, ISDN, DSL, cable, satellite and
dedicated leased lines
Sharing an Internet connection Sharing a dial-up, DSL or cable connection Building ethernet networks: wired and
wireless
Comparing the optionsConclusion
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POTS: Plain Old Telephone Service
Uses the standard phone lineUser dials up the ISP to make a
connectionSpeeds said to be 56K but always slowerInternet (IP) address is assigned at the
time of the callRequires minimal hardware and setupCosts about $14 to $20 / month for
unlimited use
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POTS
AdvantagesAvailable from
anyplaceEasy set upEasy to switch ISPUseful when travelingAll new computers
can use it
DisadvantagesSlowDialing-up and
connecting is slowTies up phone line Intermittent
connections
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ISDN: Integrated Service Digital Network
Digital version of dial-up telephoneInstalled by local phone companyRequires an ISDN card in the PC or an
external “modem”A digital call is made at the time of “need”Reliable speeds of 64-128KInternet access (ISP) a separate cost$45 metered, $120 unlimited use / mo.
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ISDN
Advantages Fast dialing (~1.5 sec) Easy to switch ISPs ISP can connect to you
(extra cost) Available in some
locations where alternatives are not
Disadvantages Expensive Intermittent connections Requires add’l hardware Requires new wiring Metered by phone co and
sometimes the ISP Difficult to get installed Works only at the site of
installation Limited availability
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DSL: Digital Subscriber Line
Runs over ordinary telephone wiresDigital signals use high frequencies not
used by analog phonesInstalled by local phone companyReliable download speeds of 128K to 7MAlways onInternet access (ISP) a separate costMonthly cost $22 for 256K to $275 for 7M
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DSL
Advantages Always on Flat fee Reliable Requires no new wiring Does not tie up phone
line Fixed IP available Can be used to host a
web site Dial-up access when
traveling often included
Disadvantages Can be tough to switch
ISPs Requires additional
hardware (DSL Router) Can be difficult to get
installed Works only at the site of
installation Limited availability Fast upload speeds cost
more
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Cable
Runs over cable TV wiring Installed by cable companyDownload speeds of 768K to 3M and higherUpload speeds slower, about 300KAlways onShared bandwidth - the more people on it, the
slower it isUnlimited use with Internet access (ISP)
included in costCosts about $50 per month
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Cable
Advantages Usually quite fast Always on Flat fee Somewhat reliable Broader availability Does not interfere with
TV
Disadvantages Shared bandwidth Requires additional
hardware (cable box) Works only at the site of
installation Upload slower than
download No choice in cable
company or ISP Dial-up access when
traveling not always included
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Satellite
Available from remote locationsTwo providers: Direcway and StarbandDownloads about 1M. Upload via satellite
up-link up to 100K.Costs: Installation ~$200 plus:
Single Win98SE or better machine: unlimited service $70/mo hardware $500
Networked machines (any OS): unlimited service$150/mo hardware $600
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Satellite
AdvantagesAvailable anyplace
that has a view of the southern sky
Always onUnlimited access
DisadvantagesHardware and
installation costsShared bandwidthCan be slow when
using a Virtual Private Network (VPN)
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Dedicated Leased Line
Fixed digital connectionBidirectional access at guaranteed speedsSpeeds range from 56K to T1 (1.5M) on
upAlways on, unmeteredISP is a separate chargeFees:
56K $80/mo, with ISP $300/mo 1.5M T1 $250/mo, with ISP $1500/mo
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Dedicated Leased Line
Advantages The most reliable
connection to the Internet Guaranteed bandwidth
and service levels Great for hosting a web
site or for managing your own security and firewalls
56K available anyplace there is a telephone
Disadvantages Expensive T1 and higher access
confined to metro. Extremely expensive in rural areas
Difficult to get installed Not easy to switch ISPs Requires dedicated
hardware
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Sharing an Internet Connection
Use one Internet connection to allow access by several machines
Products available for dial-up (POTs), DSL and cable
Most products also include a firewall increasing security
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Sharing a Dial-up Connection
AdvantagesCheapUses only one phone
lineAny number of
computers can share one line
Can be used with a network
DisadvantagesSlow. Same problem
as POTSSpeed slows as more
attempt to use the line at the same time
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Sharing a DSL or Cable Line
Share a single DSL or cable line with any number of computers
Can be used with a wired, wireless or mixed network.
Can be used to share a single Internet (IP) address on an existing network.
Hardware starts at $80
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Sharing a DSL or Cable Line
Advantages Always on Uses only one DSL or
Cable connection Any number of computers
can access the Internet simultaneously
Computers inside can be invisible to the outside
A computer inside can be a web server for the Internet
Disadvantages Requires extra
hardware Requires a network
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Building Networks
Wired EthernetAdvantages
Very high speed: 10, 100 and 1000M
More secure - requires a physical connection
Disadvantages Running wires Laptop needs a wire
Wireless (WiFi) Advantages
High speed 11M (802.11b) and higher (802.11a & g)
Wiring unnecessary Use with any computer Laptops not tethered Many laptops are wireless-
ready Disadvantages
May require a PC Card Requires extra steps to
increase security
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Wireless Connections to the Internet Networks
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Comparing the Options
Feature POTS ISDN DSL Cable Satellite 56K T-1Download
Speed<56K 128K
<128K-1.5M-7M
<768K-3M
~1M 56K 1.5M
UploadSpeed
<56K 128K<128-384K-1.5M
<256-384K
~100K 56K 1.5M
Metered No Yes-No No No No No No
Cost/mo ~$20 $45-$120$22-
$275-$?$50-$90
$70 single$150 ntwk
$80+ $250
FixedIP No Avail Often Add’l $ Add’l $ Yes Yes
ISP cost $0 $40-$150 $25 $0 $0 $300 $1500
Hardware ~$0 $600 often incl incl $500-600 $1500 $1500
Install ~$0 ~$25 ~$0 ~$0 ~$200 $380 $1750
Availability wide wide growing growing wide wide urban
All costs are approximate
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Useful Links
Handouts from this lecture with additional links: http://fpen.org/aafp/connect.html
Home networking information from Linksys: http://www.linksys.com/edu/
Home networking information from Microsoft http://www.microsoft.com/insider/networking/
The owners' manual for the broadband wireless router demonstrated in class: ftp://ftp.linksys.com/pdf/wrt54gv1.1_ug.pdf
Webopedia: An encyclopedia of technology terms http://webopedia.internet.com/