 Cable Modems - speeds, connection sharing, security, etc.
Cable modems
may be the most readily available broadband internet connection
followed closely by DSL (anyone have some stats?). They can reach
nearly every home that has access to digital cable television. At
about $40-$50 per month, cable modems are still a premium service
over traditional phone lines.
Speeds:
Cable modems boast some
of the fastest download speeds. Most cable modem companies cap the
download bandwidth at 1.5Mbps but some people have reached speeds of
up to 3 or 4 Mbps. I could count on about 500-800Mbps throughput in
a community that has had cable modems for a while. The upload speeds
are fairly slow and are limited to 64 or 128Mbps. Unlike DSL, you
can not yet purchase different service levels to increase the
bandwidth available.
Shared Bandwidth
Cable modems work by
assigning upload and download 'channels' to communities of people in
your neighborhood. Although your download speed might be capped at
1.5Mbps, that bandwidth is shared by many people in your
neighborhood. If someone runs a streaming audio server or other
server that sends a lot of data, they could tie up the upload
channel for 20 or 30 people making their Internet access much slower
than it should be.
Network Security
Cable modems put your
computer in the same 'logical' network neighborhood as your
neighbors. All the computers directly connected to a cable modem in
your neighborhood think they are on the same LAN and try to
communicate with each other. These computers then show up in
Microsoft's Internet neighborhood ready to be browsed. If network
shares are presented to your cable modem neighborhood, you can bet
that someone is going to 'browse' the neighborhood and try to access
your shares. That is one of the reasons it is SO important to have a
software or hardware firewall with a cable modem.
Sharing the connection
Most cable modem
companies will try to tell you that you need extra IP address' to
share the connection. This is a bad idea. Read
about it here
Options are
Open
Your options are complely
open when it comes to sharing your cable modem Internet
connection
One Way Cable
Modems
There are still some
one-way cable modems out there in use. These modems use a
telephone modem for the 'up' stream and the cable modem for the
'down' stream. They can not be shared with a broadband router or Microsoft ICS. Check into some of
the other software solutions for
internet sharing
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Cable Modem Sharing
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