CSCI 360CSCI 360Intro To Computer NetworksIntro To Computer Networks

INFS 361 INFS 361 Network AdministrationNetwork Administration

Bob BradleyBob Bradley

InstructorInstructor

My name is Bob BradleyMy name is Bob Bradley

Office and office hours and web page Office and office hours and web page

www.utm.edu/~bbradleywww.utm.edu/~bbradley

See web page for SyllabusSee web page for Syllabus and and timelinetimeline

CS 360CS 360 Class ? Midterm/test/final/quizesClass ? Midterm/test/final/quizes There will be programming projects. More so this semester.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…How I grade projects… This for a C, this for a B, this for an A…   Prereqs: c++ cs221 , cs200/201 Prereqs: c++ cs221 , cs200/201

Book - Computer Networks and Internets Book - Computer Networks and Internets 4th Edition4th Edition And Workbook - And Workbook - Hands-On-Networking with Internet Technologies 2nd EditionHands-On-Networking with Internet Technologies 2nd Edition Will be going though most of the book. You will need the latest edition.Will be going though most of the book. You will need the latest edition.

Will focus on Network Application Protocols and ProgrammingWill focus on Network Application Protocols and Programming• c++, c#, Javac++, c#, Java• Free MSDN developer studio - get it from the cs departmentFree MSDN developer studio - get it from the cs department

   Will be changing the schedule… Check the web often…Will be changing the schedule… Check the web often… This week Overview then Chap 1,2,3.This week Overview then Chap 1,2,3. Talk about schedule for class...Talk about schedule for class...

INFS 361INFS 361 Book - Business Data Networks and Telecommunications Book - Business Data Networks and Telecommunications 5th 5th

EditionEdition Prereqs: INFS 316Prereqs: INFS 316   Lots of quizesLots of quizes Several ProjectsSeveral Projects Midterm and FinalMidterm and Final   Will focus on Network AdministrationWill focus on Network Administration ProjectsProjects

• Microsoft Virtual PC 2004Microsoft Virtual PC 2004 Windows 2003 ServerWindows 2003 Server

• File Server, IIS Web ServerFile Server, IIS Web Server• DHCP, DNSDHCP, DNS• MailMail

LinuxLinux• Apache Web ServerApache Web Server• DHCP, DNSDHCP, DNS• SendMailSendMail

OverviewOverview Data TransmissionData Transmission Packet Transmission - packets, frames, Packet Transmission - packets, frames,

• Sniffers - like radio scannerSniffers - like radio scanner• Privacy and sniffingPrivacy and sniffing• Networks like cell phones… public can scan/receive transmissionsNetworks like cell phones… public can scan/receive transmissions

Hardware addressesHardware addresses LANS vs WANSLANS vs WANS Connection vs ConnectionlessConnection vs Connectionless InternetworkingInternetworking Protocols Protocols

• TCP/IPTCP/IP• IP - arp, bind, ip datagrams, encapsulation, icmpIP - arp, bind, ip datagrams, encapsulation, icmp

Network ApplicationsNetwork Applications Client server - sockets - DNS – E-Mail (whole weeks) – HTTP (Web), FTP, Client server - sockets - DNS – E-Mail (whole weeks) – HTTP (Web), FTP,

SMTPSMTP p2p file sharing Naptsterp2p file sharing Naptster Network security, firewalls, finalsNetwork security, firewalls, finals    Wireless - 802.11b, firewall security, rfcs, vpns, etc.Wireless - 802.11b, firewall security, rfcs, vpns, etc.

Dorm NetworkDorm Network

In 1996In 1996• UTM was one of the first Universities to UTM was one of the first Universities to

put two hard-wired network connections put two hard-wired network connections in every dorm roomin every dorm room

• network was very fastnetwork was very fast 10 MegaBit Ethernet10 MegaBit Ethernet T1 (24 Phone lines/1.5 MegaBit/Sec) T1 (24 Phone lines/1.5 MegaBit/Sec)

connection to internet connection to internet

• web pages were small and simpleweb pages were small and simple

1999 Network Slowdown1999 Network Slowdown In 1999, UTM’s network (and most University In 1999, UTM’s network (and most University

networks) became very, very slow.networks) became very, very slow. In 1999, a program called Napster came out!In 1999, a program called Napster came out! Allowed users to download and share music files Allowed users to download and share music files

(MP3s).(MP3s). When this first came out, it made our whole When this first came out, it made our whole

university network totally unusable.university network totally unusable.• You could no longer check any web pages, read email, You could no longer check any web pages, read email,

download files or do anything.download files or do anything.• The file sharing program ate up all of our bandwidth.The file sharing program ate up all of our bandwidth.

Web Page vs Music FileWeb Page vs Music File

Typical web page with small Typical web page with small graphicsgraphics• 3-3-3030KB (Kilo-Bytes)KB (Kilo-Bytes)

Typical MP3 music fileTypical MP3 music file• 33-6MB (Mega-Bytes)-6MB (Mega-Bytes)• 100s of times bigger100s of times bigger

Relative width of T1Relative width of T1• 1.5 Mega-bits/sec1.5 Mega-bits/sec• About 150 Kilo-Bytes/secAbout 150 Kilo-Bytes/sec• About 5-50 web pages/secAbout 5-50 web pages/sec• About 1 song in 20-40 secAbout 1 song in 20-40 sec

If only one person using the netIf only one person using the net

100 Web Pages

Difference in Difference in download timesdownload times

5 Web Pages

5 Songs

Note this example is speeded up, but notice the relative differences in time it takes to download web pages vs. the 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.

T1

Wanted traffic gets Wanted traffic gets bogged downbogged 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 Packet/Traffic Shaper/FilterShaper/Filter

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).

T1

Dorm NetworkDorm Network We now have over 1300 student computers We now have over 1300 student computers

connected in the dorms.connected in the dorms.

We now have a T3/DS3We now have a T3/DS3 28 T1s or 672 phone lines28 T1s or 672 phone lines 45 MegaBits/Sec45 MegaBits/Sec

Relative size of T1 vs Relative size of T3Relative size of T1 vs Relative size of T3

Bandwidth of ProtocolsBandwidth of Protocols

Even with our DS3 connection, this chart Even with our DS3 connection, this chart shows what happens to our bandwidth if shows what happens to our bandwidth if we turn off our traffic/packet shaperwe turn off our traffic/packet shaper

Bandwidth with filter turned on

Bandwidth when filter is turned off

NetEnforcerNetEnforcer

The Real-Time Traffic MonitorThe Real-Time Traffic Monitor   

NetEnforcerNetEnforcerGet monthly updated rules used to filter the traffic

NetEnforcerNetEnforcer

Protocol Bandwidth Percentage ScreenProtocol Bandwidth Percentage Screen

How Not To Get Sued By The How Not To Get Sued By The RIAA For File-SharingRIAA For File-Sharing

(And Other Ideas to Avoid Being Treated Like a Criminal)(And Other Ideas to Avoid Being Treated Like a Criminal)

The Recording Industry Association of America (RIAA) The Recording Industry Association of America (RIAA) announced on June 25, 2003, that it will begin suing users announced on June 25, 2003, that it will begin suing users of peer-to-peer (P2P) file-sharing systems within the next of peer-to-peer (P2P) file-sharing systems within the next few weeks. According to the announcement, the RIAA will few weeks. According to the announcement, the RIAA will be targeting users who upload/share "substantial" amounts be targeting users who upload/share "substantial" amounts of copyrighted music. The RIAA has stated that it will of copyrighted music. The RIAA has stated that it will choose who to sue by using software that scans users' choose who to sue by using software that scans users' publicly available P2P directories and then identifies the ISP publicly available P2P directories and then identifies the ISP of each user. Then, using the Digital Millennium Copyright of each user. Then, using the Digital Millennium Copyright Act (DMCA), the RIAA will subpoena the ISP for each user's Act (DMCA), the RIAA will subpoena the ISP for each user's name, address, and other personal information in order to name, address, and other personal information in order to sue that user. sue that user.

http://www.eff.org/IP/P2P/howto-notgetsued.phphttp://www.eff.org/IP/P2P/howto-notgetsued.php