Transcript Cable - Chipps

Cable
Last Update 2010.01.16
1.7.0
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
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Objectives of This Section
• Learn
– How the cable TV system can be used to
access a corporate network
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
2
Context
Layer
Network Type
1
WAN
Copyright 2000-2010 Kenneth M. Chipps Ph.D. www.chipps.com
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Layers
• As a layer 1 technology a Cable data line
requires something at layers 2 through 7 in
order to operate
• Typically this is
– Layer 2
• PPPoE
– Layer 3 through 7
• TCP/IP and a VPN
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
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Current Use
• Current cable systems can provide all
aspects of connectivity to a business
including phone service, Internet access,
and TV
• Keep in mind that this is not a dedicated
data line
• In order to connect to another site the
traffic will at some point have to cross the
Internet
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
5
Speeds
• Speeds on current cable systems are fast
enough to support a large number of users
• For example Comcast states their
business class connection has 50 Mbps
down and 10 Mbps up
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
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Setup
• One of the nice things about this
technology from the standpoint of the
WAN manager is that there is nothing that
must be done on the customer end to
setup this kind of data line
• Just call the provider
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
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Security
• As a shared media security is a problem
for cable systems
• Most systems use DOCSIS to provide
some security
• As an always on media the site must be
protected just like any other site
• This requires a firewall running on a single
machine or a small firewall to protect the
site
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
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Security
• A better solution is to deploy these along
with a VPN solution
Copyright 2000-2010 Kenneth M. Chipps Ph.D.
www.chipps.com
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