Networks - Department of Math and Computer Science

Networks - Department of Math and Computer Science

Networks
Dr. M. Anthony Kapolka III
CS 115
Wilkes University
Source:Information Technology and Society, Laudon et. al., Course Technology, 1996
Internet Connectivity
Source: Using Information Technology, Williams, Sawyer, Hutchinson, Irwin, 1997
www.internetworldstats.com
E-Mail
Source: Guide to Medical Informatics, The Internet, and Telemedicine, Coiera, Chapman Hall, 1997
Voice Mail
Source: Guide to Medical Informatics, The Internet, and Telemedicine, Coiera, Chapman Hall, 1997
Communication
Same Time Different Time
Same Place
Meeting
Note
Different Place
Phone Call
Letter
Communication Channels
Source: Guide to Medical Informatics, The Internet, and Telemedicine, Coiera, Chapman Hall, 1997
Network
Layers
Source: NOSintro, Wade, Dowermain Ltd., 1992
Network Layers
Source: Webmaster’s Handbook, Fisher, Primera Publishing, 1996/
Application
Layer
Source: NOSintro, Wade, Dowermain Ltd., 1992
Physical
Layer
Video Phones: Fax machines
Source:Information Technology and Society, Laudon et. al., Course Technology, 1996
Twisted Pair
Source: Discovering Computers, Shelley, Cashman, Wagonner, Course Technologies, 1998.
Cable
Source: Net Gains, O’Malley, Popular Science, April 1998
Coaxial Cable
Source: Discovering Computers, Shelley, Cashman, Wagonner, Course Technologies, 1998.
Fiberoptic
Source: Discovering Computers, Shelley, Cashman, Wagonner, Course Technologies, 1998.
Radio Channel
Source: Wireless Digital Communication, McDermott, TAPR, 1996.
Radio Spectrum
Source: Using Information Technology, Williams, Sawyer, Hutchinson, Irwin, 1997
Analog vs. Digital Signals
Source: Using Information Technology, Williams, Sawyer, Hutchinson, Irwin, 1997
Modems
Source: Using Information Technology, Williams, Sawyer, Hutchinson, Irwin, 1997
How Modems Work
Source: Computer Confluence, Beekman, Addison Wesley, 1998
Asynchronous Transfer
Source: Using Information Technology, Williams, Sawyer, Hutchinson, Irwin, 1997
Asynchronous
Source: Understanding Computers, Parker, Dryden Exact, 1996
Synchronous Transfer
Source: Using Information Technology, Williams, Sawyer, Hutchinson, Irwin, 1997
Synchronous
Source: Understanding Computers, Parker, Dryden Exact, 1996
Serial vs. Parallel
Source: Understanding Computers, Parker, Dryden Exact, 1996
Making Channels
Source: Guide to Medical Informatics, The Internet, and Telemedicine, Coiera, Chapman Hall, 1997
Circuit Switching
Source: Computers and the Information Society, Radlow, Boyd & Fraiser, 1995
Packet Switching
Source: Computers and the Information Society, Radlow, Boyd & Fraiser, 1995
Network
Layers
Source: NOSintro, Wade, Dowermain Ltd., 1992
Multiplexing
Source: Guide to Medical Informatics, The Internet, and Telemedicine, Coiera, Chapman Hall, 1997
Digital Subscriber Line
Source: Net Gains, O’Malley, Popular Science, April 1998
Source: Computers Inside and Out, Lauckner and Lintner, Pippin, 1996.
Networks
LAN - Local Area Network
Source: Computer Confluence, Beekman, Addison Wesley, 1998
n, Irwin, 1997
Source: Using Information Technology, Williams, Sawyer, Hutchinso
Star
Topology
n, Irwin, 1997
Source: Using Information Technology, Williams, Sawyer, Hutchinso
Ring Topology
n, Irwin, 1997
Source: Using Information Technology, Williams, Sawyer, Hutchinso
Bus
Topology
Intranets
Source: Guide to Medical Informatics, The Internet, and Telemedicine, Coiera, Chapman Hall, 1997
IP
Masquerading
IP
Masquerading
Source: Computer Confluence,
Beekman, Addison Wesley, 1998
A Network Firewall
Network
Layers
Source: NOSintro, Wade, Dowermain Ltd., 1992
Function of a Firewall
Source: Computers and the Information Society, Radlow, Boyd & Fraser,
WAN - Wide Area Network
Source: Computer Confluence, Beekman, Addison Wesley, 1998
Terrestrial Repeaters
Source: Computers and the Information Society, Radlow, Boyd & Fraiser, 1995
Radio Spectrum
Source: UIT, Sawyer, Williams, Hutchinson, IRWIN, 1997
Radio Spectrum
Source: UIT, Sawyer, Williams, Hutchinson, IRWIN, 1997
n, Irwin, 1997
Source: Using Information Technology, Williams, Sawyer, Hutchinso
Cell
Phones
Satellite Repeater
Source: Computers and the Information Society, Radlow, Boyd & Fraiser, 1995
Arthur C. Clarke
Source: Computer Confluence, Beekman, Addison Wesley, 1998
Satellites
Source: Understanding Computers, Parker, Dryden Exact, 1996
Satellite
Source: Net Gains, O’Malley, Popular Science, April 1998
Speed Comparison
Source: Net Gains, O’Malley, Popular Science, April 1998
WAN - Wide Area Network
Source: Computer Confluence, Beekman, Addison Wesley, 1998
Source: Discovering Computers, Shelley, Cashman, Wagonner, Course Technologies, 1998.
Source: http://www.jeffkennedyassociates.com:16080/connections/concept/images
Bandwidth Bottlenecks
Problem: Network is too slow.
Typical
Solution: Add more bandwidth.
Problem: Requires demand to
outpace supply.
Internet (TCP/IP, Ethernet)

Collisions
– dropped packets
– stay away!

More lines - more cost.

Transport standards must be honored
everywhere.
Some Ideas
Identify priority and requirements
of network applications.
Reserve bandwidth in advance.
Manage redundant data.
Source: Breaking Bandwidth Bottlenecks, BYTE Magazine, May 1998.
Source: Breaking Bandwidth Bottlenecks, BYTE Magazine, May 1998.
Source: Breaking Bandwidth Bottlenecks, BYTE Magazine, May 1998.
Possible Packet Redundancy
e-mail
• Peer to Peer
mailing list
• Narrowcast
newsgroup
• Broadcast (Multicast)
Next: Data Security
Source: Understanding Computers, Parker, Dryden Exact, 1996