Making Sense of Your
Connectivity Options
Paul Kleeberg, M.D.
American Academy of Family
Physicians Scientific Assembly
October 3rd, 2003
New 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 options
Conclusion
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POTS: Plain Old Telephone
Service
Uses the standard phone line
User dials up the ISP to make a
connection
Speeds said to be 56K but always slower
Internet (IP) address is assigned at the
time of the call
Requires minimal hardware and setup
Costs about $14 to $20 / month for
unlimited use
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POTS
Advantages
Available from
anyplace
Easy set up
Easy to switch ISP
Useful when traveling
All new computers
can use it
Disadvantages
Slow
Dialing-up and
connecting is slow
Ties up phone line
Intermittent
connections
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ISDN: Integrated Service
Digital Network
Digital version of dial-up telephone
Installed by local phone company
Requires an ISDN card in the PC or an
external “modem”
A digital call is made at the time of “need”
Reliable speeds of 64-128K
Internet 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 wires
Digital signals use high frequencies not
used by analog phones
Installed by local phone company
Reliable download speeds of 128K to 7M
Always on
Internet access (ISP) a separate cost
Monthly 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 company
Download speeds of 768K to 3M and higher
Upload speeds slower, about 300K
Always on
Shared bandwidth - the more people on it, the
slower it is
Unlimited use with Internet access (ISP)
included in cost
Costs 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
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included
Satellite
Available from remote locations
Two providers: Direcway and Starband
Downloads 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
Advantages
Disadvantages
Available anyplace
that has a view of the
southern sky
Always on
Unlimited access
Hardware and
installation costs
Shared bandwidth
Can be slow when
using a Virtual Private
Network (VPN)
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Dedicated Leased Line
Fixed digital connection
Bidirectional access at guaranteed speeds
Speeds range from 56K to T1 (1.5M) on
up
Always on, unmetered
ISP is a separate charge
Fees:
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
Advantages
Disadvantages
Cheap
Uses only one phone
line
Any number of
computers can share
one line
Can be used with a
network
Slow. Same problem
as POTS
Speed 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 Ethernet
Advantages
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 wirelessready
 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
DSL
Cable Satellite 56K
POTS
ISDN
<56K
128K
<56K
128K
No
Yes-No
Cost/mo
~$20
$45-$120
FixedIP
ISP cost
Hardware
Install
Availability
No
Avail
$0
$40-$150
$25
$0
~$0
$600
often incl
~$0
~$25
wide
wide
Feature
Download
Speed
Upload
Speed
Metered
<128K- <768K~1M
3M
1.5M-7M
<128<256384K~100K
384K
1.5M
No
No
No
$70 single
$22$50-$90
$150 ntwk
$275-$?
AddХl $
AddХl $
Often
T-1
56K
1.5M
56K
1.5M
No
No
$80+
$250
Yes
Yes
$0
$300
$1500
incl
$500-600
$1500
$1500
~$0
~$0
~$200
$380
$1750
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/
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