Wireshark (aka Ethereal) - Nanog

57 Pages·2007·3.05 MB·English

Wireshark
(aka Ethereal)
Aamer Akhter / [email protected]
ECMD, cisco Systems
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What is Wireshark
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Free Open Source Network Protocol Analyzer
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Multi-platform: Runs on Windows, Linux, Solaris,
NetBSD, FreeBSD
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CLI as well as Graphical display
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100’s of protocols supported
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Acknowledgements
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Gerald Combs, creator, lead developer – 1998
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Guy Harris
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Gilbert Ramirez
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Many, many contributors
http://anonsvn.wireshark.org/wireshark/trunk/AUTHORS
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libpcap folks
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Winpcap folks
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CACE Technologies
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How is Wireshark Used today?
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Troubleshooting
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Performance issues
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Security Analysis
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Protocol Learning Tool
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Protocol Development
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Wireshark Website
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http://www.wireshark.org
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Formerly ethereal.com
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Source tarball
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SVN repository
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Multi-platform compiled
sources
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Documentation
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Wireshark Wiki
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http://wiki.wireshark.org/
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Protocol reference
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Discussion on various
network protocols and
their function operation
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Growing sample pcap
library
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Basic
Components
CCaappttuurreedd FFrraammee
FFiilltteerr SSppeecc
FFrraammeess tthhaatt mmaattcchh
FFiilltteerr SSppeecc
PPrroottooccooll DDiisssseeccttiioonn ooff
sseelleecctteedd ffrraammee
HHeexx vviieeww ooff ffrraammee
hhiigghhlliigghhtteedd,, sseelleeccttiioonn
ffrroomm pprroottooccooll ddiisssseeccttiioonn
iiss aa aallssoo hhiigghhlliigghhtteedd
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Acquiring Packets (capturing)
Select
Capture->Interfaces…
Pick which Interface to Capture
Real-time stats are shown with
basic breakdown of captured packets
Clock on Stop to
Stop and Analyze in detail
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Capture Options
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Allow user to select ‘how’
the capture is done
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Capture Filters
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Where to store capture file
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Real-time Capture
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When to stop Capturing
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Security- Capturing Packets
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Capturing generally super-user capability
BSD does not require SU to capture in promiscious
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Have been number of security related issues
Large number of dissectors from variety of people
Large infrastructure code (GTK, etc)
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For pure capture, ‘tshark’ in capture-only mode or
‘tcpdump’ might be better option
Analysis in Wireshark
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