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CS335 Networking & Network Administration. Introductions History of Networks Simple Computer Networks. Timothy Welch. Network manager – La Grande School District Bought first computer in 1986 – Atari 1040st Macintoshes – 1990 Big Sky Telegraph 300 baud modem Text file transfers
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CS335 Networking &Network Administration Introductions History of Networks Simple Computer Networks
Timothy Welch • Network manager – La Grande School District • Bought first computer in 1986 – Atari 1040st • Macintoshes – 1990 • Big Sky Telegraph • 300 baud modem • Text file transfers • 1995 introduced to www/mosaic/netscape
Timothy Welch – bio (cont.) • NSF grant at EOU • Web development • Private networking and web serving • Database driven web development • 1998 LGSD network installed • Development of LGSD network and data development • Novell, Windows, Macintosh, Linux, Cisco
Enough about me • What about you as CS students? • Course expectations? • Where do we begin?
History of computer networks • Resource sharing • ARPAnet (Advanced Research Project Agency) 1960’s • Packet switching technology • By the 70’s internetworking emerged • Internet research 80’s & 90’s
Ping • A utility to determine whether a specific IP address is accessible. It works by sending a packet to the specified address and waiting for a reply. PING is used primarily to troubleshoot Internetconnections. There are many freeware and shareware Ping utilities available for personal computers. It is often believed that "Ping" is an abbreviation for Packet Internet Groper, but Ping's author has stated that the names comes from the sound that a sonar makes.
Probing the internet • Ping • Is a host reachable? • Response time consistent • IP Address or domain name
Using ping • We had a network segment that was acting very slow. Used ping to verify packet loss. Helped us find a problem on the router. • Find hosts • Test trip length • Test for connectivity
Traceroute • trās´rowt) (n.) A utility that traces a packet from your computer to an Internethost, showing how many hops the packet requires to reach the host and how long each hop takes. If you're visiting a Web site and pages are appearing slowly, you can use traceroute to figure out where the longest delays are occurring. The original traceroute is a UNIXutility, but nearly all platforms have something similar. Windows includes a traceroute utility called tracert. In Windows, you can run tracert by selecting Start->Run…, and then entering tracert followed by the domain name of the host. • Traceroute utilities work by sending packets with low time-to-live (TTL) fields. The TTL value specifies how many hops the packet is allowed before it is returned. When a packet can't reach its destination because the TTL value is too low, the last host returns the packet and identifies itself. By sending a series of packets and incrementing the TTL value with each successive packet, traceroute finds out who all the intermediary hosts are.
Traceroute • Finding network hops • http://www.net.cmu.edu/cgi-bin/netops.cgi • EOU network doesn’t allow ping (ICMP Echo Request) traffic outside the network. • ICMP (internet control message protocol)
Traceroute Result from • http://www.net.cmu.edu/cgi-bin/netops.cgi • 1 POD-C-CYH-VL4.GW.CMU.NET (128.2.4.48) 0.474 ms 0.378 ms 0.349 ms • 2 CORE0-POD-C-CYH.GW.CMU.NET (128.2.0.186) 0.490 ms 0.477 ms 0.430 ms • 3 HYPER-VL502.GW.CMU.NET (128.2.33.233) 0.788 ms 0.690 ms 0.628 ms • 4 bar-cmu-ge-4-0-0-1.3rox.net (192.88.115.185) 0.485 ms 0.401 ms 0.398 ms • 5 beast-bar-pc1-1.3rox.net (192.88.115.77) 0.424 ms 0.240 ms 0.236 ms • 6 abilene-psc.abilene.ucaid.edu (192.88.115.124) 10.077 ms 10.079 ms 9.988 ms • 7 nycmng-washng.abilene.ucaid.edu (198.32.8.84) 14.237 ms 14.189 ms 14.243 ms • 8 chinng-nycmng.abilene.ucaid.edu (198.32.8.82) 34.398 ms 34.370 ms 34.242 ms • 9 iplsng-chinng.abilene.ucaid.edu (198.32.8.77) 314.268 ms 304.626 ms 335.171 ms • 10 kscyng-iplsng.abilene.ucaid.edu (198.32.8.81) 62.792 ms 47.301 ms 62.392 ms • 11 dnvrng-kscyng.abilene.ucaid.edu (198.32.8.13) 68.743 ms 70.168 ms 57.887 ms • 12 snvang-dnvrng.abilene.ucaid.edu (198.32.8.1) 82.692 ms 82.668 ms 82.740 ms • 13 pos-1-0.core0.eug.oregon-gigapop.net (198.32.163.17) 94.933 ms 94.930 ms 94.989 ms • 14 nero.eug.oregon-gigapop.net (198.32.163.151) 95.110 ms 95.294 ms 95.186 ms • 15 ptck-core2-gw.nero.net (207.98.64.2) 97.494 ms 97.318 ms 97.298 ms • 16 eou-car1-gw.nero.net (207.98.64.22) 110.236 ms 110.092 ms 109.994 ms 17 * * * 18 * * * 19 * * * 20 * * * 21 * * * 22 * * * 23 * * * 24 * * * 25 * * * 26 * * * 27 * eou-gw.eou.EDU (140.211.3.5) 111.158 ms !X * 28 * * * 29 * * * Error!Timed out while processing: /usr/sbin/traceroute 140.211.60.20.
Traceroute • 1 POD-C-VL4.GW.CMU.NET (128.2.4.1) 0.288 ms 0.213 ms 0.177 ms • 2 CORE0-POD-C-NH.GW.CMU.NET (128.2.0.194) 0.213 ms 0.188 ms 0.183 ms • 3 POD-I-CYH-VL940.GW.CMU.NET (128.2.0.205) 0.218 ms 0.210 ms 0.206 ms • 4 bar-cmu-ge-4-0-0-2.3rox.net (192.88.115.185) 0.331 ms 0.300 ms 0.288 ms • 5 beast-bar-pc1-1.3rox.net (192.88.115.77) 0.252 ms 0.171 ms 0.197 ms • 6 abilene-psc.abilene.ucaid.edu (192.88.115.124) 9.866 ms 9.844 ms 25.241 ms • 7 nycmng-washng.abilene.ucaid.edu (198.32.8.84) 25.461 ms 14.078 ms 14.181 ms • 8 chinng-nycmng.abilene.ucaid.edu (198.32.8.82) 44.750 ms 37.361 ms 34.231 ms • 9 iplsng-chinng.abilene.ucaid.edu (198.32.8.77) 38.024 ms 38.007 ms 46.806 ms • 10 kscyng-iplsng.abilene.ucaid.edu (198.32.8.81) 47.258 ms 47.162 ms 47.968 ms • 11 dnvrng-kscyng.abilene.ucaid.edu (198.32.8.13) 57.907 ms 57.769 ms 68.569 ms • 12 snvang-dnvrng.abilene.ucaid.edu (198.32.8.1) 82.581 ms 88.631 ms 82.781 ms • 13 pos-1-0.core0.eug.oregon-gigapop.net (198.32.163.17) 94.925 ms 94.786 ms 94.713 ms • 14 nero.eug.oregon-gigapop.net (198.32.163.151) 94.999 ms 94.931 ms 94.978 ms • 15 ptck-core2-gw.nero.net (207.98.64.2) 97.186 ms 97.280 ms 97.254 ms • 16 eou-car1-gw.nero.net (207.98.64.22) 110.047 ms 109.972 ms 110.053 ms
Lab Exercises • Ping • Traceroute programs • http://network-tools.com/ • History of the Internet • http://www.davesite.com/webstation/net-history.shtml • http://www.isoc.org/internet/history/brief.shtml
Lets go to the lab • Testing out ping • Traceroute • History of the internet • Homework – Read the 2 web pages that are on the previous slide. Write a one page summary on the history of the internet as you understand it from this brief overview. • Due Tuesday.