Download CSCI 360 Intro To Computer Networks INFS 361 Network

CSCI 360
Intro To Computer Networks
INFS 361
Network Administration
Bob Bradley
Instructor
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My name is Bob Bradley
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Office and office hours and web page
www.utm.edu/~bbradley
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See web page for Syllabus and
timeline
CS 360
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Class ? Midterm/test/final/quizes
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There will be programming projects. More so this semester.
How I grade projects… This for a C, this for a B, this for an A…
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Prereqs: c++ cs221 , cs200/201
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Book - Computer Networks and Internets 4th Edition
And Workbook - Hands-On-Networking with Internet Technologies 2nd Edition
Will be going though most of the book. You will need the latest edition.
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Will focus on Network Application Protocols and Programming
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c++, c#, Java
Free MSDN developer studio - get it from the cs department
Will be changing the schedule… Check the web often…
This week Overview then Chap 1,2,3.
Talk about schedule for class...
INFS 361
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Book - Business Data Networks and Telecommunications 5th
Edition
Prereqs: INFS 316
Lots of quizes
Several Projects
Midterm and Final
Will focus on Network Administration
Projects
• Microsoft Virtual PC 2004
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Windows 2003 Server
• File Server, IIS Web Server
• DHCP, DNS
• Mail
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Linux
• Apache Web Server
• DHCP, DNS
• SendMail
Overview
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Data Transmission
Packet Transmission - packets, frames,
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Sniffers - like radio scanner
Privacy and sniffing
Networks like cell phones… public can scan/receive transmissions
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TCP/IP
IP - arp, bind, ip datagrams, encapsulation, icmp
Hardware addresses
LANS vs WANS
Connection vs Connectionless
Internetworking
Protocols
Network Applications
Client server - sockets - DNS – E-Mail (whole weeks) – HTTP (Web), FTP,
SMTP
p2p file sharing Naptster
Network security, firewalls, finals
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Wireless - 802.11b, firewall security, rfcs, vpns, etc.
Dorm Network
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In 1996
• UTM was one of the first Universities to
put two hard-wired network connections
in every dorm room
• network was very fast
10 MegaBit Ethernet
 T1 (24 Phone lines/1.5 MegaBit/Sec)
connection to internet
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• web pages were small and simple
1999 Network Slowdown
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In 1999, UTM’s network (and most University
networks) became very, very slow.
In 1999, a program called Napster came out!
Allowed users to download and share music files
(MP3s).
When this first came out, it made our whole
university network totally unusable.
• You could no longer check any web pages, read email,
download files or do anything.
• The file sharing program ate up all of our bandwidth.
Web Page vs Music File
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Typical web page with small
graphics
• 3-30KB (Kilo-Bytes)
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Typical MP3 music file
• 3-6MB (Mega-Bytes)
• 100s of times bigger
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Relative width of T1
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1.5 Mega-bits/sec
About 150 Kilo-Bytes/sec
About 5-50 web pages/sec
About 1 song in 20-40 sec
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If only one person using the net
Difference in
download times
Note this example is speeded
up, but notice the relative
differences in time it takes to
download web pages vs. the
songs.
T1
5 Web Pages
100 Web Pages
5 Songs
Also note, most file sharing
programs typically share out 5
or more songs at a time, so
multiply this by every user
using a file sharing program.
Wanted traffic gets
bogged down
With a steady stream of large
music files coming and going,
the “pipe” gets bogged down.
Email and web pages have to
wait in line and it is a first
come first server system.
T1
Packet/Traffic
Shaper/Filter
T1
A packet shaper/traffic filter
reserves some of the
channels, so that wanted
traffic (like web pages and
email) can still get though
without having to wait on the
unwanted traffic (file/music
sharing).
Dorm Network
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We now have over 1300 student computers
connected in the dorms.
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We now have a T3/DS3
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28 T1s or 672 phone lines
45 MegaBits/Sec
Relative size of T1 vs Relative size of T3
Bandwidth of Protocols
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Even with our DS3 connection, this chart
shows what happens to our bandwidth if
we turn off our traffic/packet shaper
Bandwidth with filter
turned on
Bandwidth when filter is
turned off
NetEnforcer
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The Real-Time Traffic Monitor
NetEnforcer
Get monthly updated rules used to filter the traffic
NetEnforcer
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Protocol Bandwidth Percentage Screen
How Not To Get Sued By The
RIAA For File-Sharing
(And Other Ideas to Avoid Being Treated Like a Criminal)
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The Recording Industry Association of America (RIAA)
announced on June 25, 2003, that it will begin suing users
of peer-to-peer (P2P) file-sharing systems within the next
few weeks. According to the announcement, the RIAA will
be targeting users who upload/share "substantial" amounts
of copyrighted music. The RIAA has stated that it will
choose who to sue by using software that scans users'
publicly available P2P directories and then identifies the ISP
of each user. Then, using the Digital Millennium Copyright
Act (DMCA), the RIAA will subpoena the ISP for each user's
name, address, and other personal information in order to
sue that user.
http://www.eff.org/IP/P2P/howto-notgetsued.php