Transcript CS335 Networking & Network Administration

CS335
Networking &
Network Administration
Introductions
History of Networks
Simple Computer Networks
Timothy Welch
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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.)
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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
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What about you as CS students?
Course expectations?
Where do we begin?
History of computer networks
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Resource sharing
ARPAnet (Advanced Research Project
Agency) 1960’s
Packet switching technology
By the 70’s internetworking emerged
Internet research 80’s & 90’s
Growth of the Internet
Ping
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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 Internet connections.
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
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Ping
Is a host reachable?
Response time consistent
IP Address or domain name
Ping commands
Using ping
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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
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trās´rowt) (n.) A utility that traces a packet from your computer to an
Internet host, 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 UNIX
utility, 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
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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)
Windows tracert
Traceroute Result from
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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
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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
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Ping
Traceroute programs
http://network-tools.com/
History of the Internet
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http://www.davesite.com/webstation/nethistory.shtml
http://www.isoc.org/internet/history/brief.shtml
Lets go to the lab
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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.