70 likes | 244 Vues
COMP 3630 - The Internet. Name: Dr. Joseph NG Office: R707 (Run Run Shaw Building) Phone: 2339-7864 Email: jng@comp.hkbu.edu.hk HomePage: http://www.comp.hkbu.edu.hk/~jng ICQ: I am not going to tell you! Planned Conference Trip: November 30 --- December 5 (Phoenix, Arizona, U.S.A.)
E N D
COMP 3630 - The Internet • Name: Dr. Joseph NG • Office: R707 (Run Run Shaw Building) • Phone: 2339-7864 • Email: jng@comp.hkbu.edu.hk • HomePage: http://www.comp.hkbu.edu.hk/~jng • ICQ: I am not going to tell you! • Planned Conference Trip: • November 30 --- December 5 (Phoenix, Arizona, U.S.A.) • Guest Lecture by Mr. Y. K. Chan on December 3.
COMP 3630 - The Internet • Subject Contents (4 weeks left) • The Cyber Map Project • Use of ping, traceroute from UNIX, and tracert from NT • Internet application using cgi or perl • Internet Applications Case Studies • Search Engines (Yahoo vs. Lycos) • Interactive TV (iTV) • Emerging Technologies leading to Electronic Commerce • Hands-on Experience for PGP (Y.K. Chan)
COMP 3630 - The Internet • The Cyber Map Project • Project Descriptions • Given the host address of the Top-22 Universities in U.S.A.; • Use traceroute (unix) or tracert (NT) to find out the routes from HKBU to each of the address and record the gateways in between; • Using the ping command to estimate the round trip delay from HKBU to each gateway; • Construct a graph to represent the connectivity between HKBU and these 25 Universities; • The graph is updated automatically and periodically; • The delay and connectivity information is made available through a web page;
1. Massachusetts Inst. of Technology 2. Stanford University (CA) 2. University of California Berkeley 4. California Institute of Technology 4. University of Illinois Urbana-Champaign 6. University of Michigan Ann Arbor 7. Carnegie Mellon University (PA) 7. Cornell University (NY) 7. Georgia Institute of Technology 10. University of Texas Austin 11. Purdue University West Lafayette (IN) 12. Princeton University (NJ) 12. University of Wisconsin Madison 14. Johns Hopkins University (MD) 14. Northwestern University (IL) 14. Pennsylvania State University 14. Rensselaer Polytechnic Inst. (NY) 18. Rice University (TX) 18. Texas A&M University College Station 18. University of California Los Angeles 18. University of Minnesota Twin Cities 18. Virginia Tech COMP 3630 - The Internet • The Cyber Map Project • Top-22 Universities of U.S.A. • http://www.usnews.com/usnews/edu/college/rankings/cat13wi.htm (courtesy to US News)
COMP 3630 - The Internet • The Cyber Map Project • Useful commands from unix and Windows NT • ping -- ping utilizes the ICMP protocol's ECHO_REQUEST datagram to elicit an ICMP ECHO_RESPONSE from the specified host or network gateway. • traceroute -- traceroute in unix and tracert in Windows NT provide the same function. Traceroute utilizes the IP protocol `time to live' field and attempts to elicit an ICMP TIME_EXCEEDED response from each gateway along the path to some host. • netstat -- netstat basically shows the network status. Depending on the options you select, it displays the state of all sockets and all routing table entries; normally only interface, host, network and default routes are shown. Note: consult the man pages for these commands.
COMP 3630 - The Internet • The Cyber Map Project • Use Yahoo or Lycos and search for traceroute and related applications and see if you have any new idea in working on your Cyber Map project. • For Examples (from Lycos) • NeoTrace • GTrace • VisualRoute • Cybergeography -- a cool site (http://www.cybergeography.org/) • Article: “MAPPING THE INTERNETWITH TRACEROUTE” by Jack Rickard • Type in “traceroute” from Yahoo will give you a list of traceroute servers.
COMP 3630 - The Internet • The Cyber Map Project • Programming • Although you can easily find the source code of “ping” and “traceroute” from the web or from the book “unix network programming” by Richard Stevens, you may want to do the project in a quick and dirty way by simply writing a C program with and make use of the “system” call. • So call traceroute from your program and redirect the output to a tmp file, and later on read back this tmp file and get the gateway information. • Use “ping” to update the delay information automatically and periodically. • Design a simple web page for query.