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T.Sharon-A.Frank1
Internet Resources Discovery (IRD)
Classic IRD Tools
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Classic IRD Tools
• Telnet Interface
• Archie
• Gopher/Veronica
• WAIS
• X.500/LDAP
• Netfind
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Telnet Interface
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Archie (1)
• Service for indexing ftp file names.
• Usually replicated to allow more users to use the database.
• FAQ: http://www.ou.edu/research/electron/internet/archifaq.htm
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Archie (2)
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Archie (3)
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Gopher/Veronica (1)
• Gopher is a directory of files, file directories and services.
• Veronica is the uniform user interface.
• Veronica’s user interface is based on menus, which offer searches on certain subjects.
• Once a resource is found - the user can access it directly, without invoking intermediate programs (e.g. ftp, telnet).
• Still around - gopher://gopher.floodgap.com/
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Gopher (2)
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WAIS (1)
• WAIS - Wide Area Information Servers
• Provides a full text index and keywords search services on documents.
• WAIS is based on Z39.50 ANSI standard for bibliographic information.
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WAIS (2)
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X.500/LDAP (1)• X.500 standards define a specification for a rich,
global, distributed directory.• Directory is based on hierarchically named
information objects.• Users can browse and search directory using
arbitrary fields.• LDAP - Lightweight Directory Access Protocol• Information: http://
www.kingsmountain.com/ldapRoadmap.shtml• Example: http://ldap.utexas.edu:8888/M
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X.500 (2)
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Netfind (1)
• Provides a White Pages service.
• Used for locating information on users.
• Uses a lot of network tools/databases.– finger– whois– mail protocol (SMTP)
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Netfind (2)
• http://ds.carnet.hr/netfind/indexe.html
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Netfind (3)
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Netfind: Information Gathering Framework
1. Information Source Selection
2. Information Collection
3. Information Filtering
4. Combining Heterogeneous Information
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Netfind Search (1)Domain cc.biu.ac.il returns:
( 0) Doing fallback lookup for ldap.tcp.cc.biu.ac.il.( 0) Doing fallback lookup for ph.tcp.cc.biu.ac.il.( 0) Doing fallback lookup for whois.tcp.cc.biu.ac.il.( 0) Doing fallback lookup for ldap.cc.biu.ac.il.( 0) Doing fallback lookup for whois.cc.biu.ac.il.( 0) Doing fallback lookup for ph.cc.biu.ac.il.( 0) SMTP_Finger_Search: checking domain cc.biu.ac.ilThe domain 'cc.biu.ac.il' does not run its own name servers,
and there is no aliased domain IP address/CNAME/MX record forthis domain -> Skipping domain search phase for this domain.
PHASE [host search]:0. ashur.cc.biu.ac.il1. alon.cc.biu.ac.il2. shikma.cc.biu.ac.il3. brosh.cc.biu.ac.il( 0) SMTP_Finger_Search: checking host ashur.cc.biu.ac.il( 1) SMTP_Finger_Search: checking host alon.cc.biu.ac.il( 2) SMTP_Finger_Search: checking host shikma.cc.biu.ac.il( 3) SMTP_Finger_Search: checking host brosh.cc.biu.ac.il( 0) read timed out( 3) read timed out( 1) read timed out
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Domain cs.biu.ac.il returns:
( 0) LookupAndFillInDomInfo: got address of domain: cs.biu.ac.il (132.70.1.24)( 0) Doing fallback lookup for ldap.tcp.cs.biu.ac.il.( 0) Doing fallback lookup for ph.tcp.cs.biu.ac.il.( 0) Doing fallback lookup for whois.tcp.cs.biu.ac.il.( 0) Doing fallback lookup for ldap.cs.biu.ac.il.( 0) Doing fallback lookup for whois.cs.biu.ac.il.( 0) Doing fallback lookup for ph.cs.biu.ac.il.( 0) SMTP_Finger_Search: checking domain cs.biu.ac.ilMail for Prof. J. B. Muskat is forwarded to [email protected]: this is a domain mail forwarding arrangement - so mail intended
for "muskat" should be addressed to"[email protected]"rather than "[email protected]".
( 0) SMTP_Finger_Search: checking host sunbeam.cs.biu.ac.il
SYSTEM: sunbeam.cs.biu.ac.ilLogin name: muskat In real life: Prof. J. B. MuskatDirectory: /u/segel/muskat Shell: /bin/TcshLast login Wed Jan 7 10:29 on ttyp1 from sunlightNew mail received Thu Mar 19 19:03:54 1998; unread since Thu Mar 19 17:38:40 1998No Plan.
FINGER SUMMARY:- The most promising email address for "muskat" based on the above finger search is [email protected].
Netfind Search (2)
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IRD Data Design Choices
System Granularity Distribution
Archie FilesDistributed
Among Servers
Gopher Services, FilesDistributed
Among Servers
WAIS DocumentsLocal to eachWAIS Server
X.500 VariesDistributed
Among Servers
Netfind UsersDistributed
Among Hosts
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IRD Metadata Design Choices
System Granularity Distribution
Archie File-namesCentralized and
Replicated
Gopher VariesDistributed
Among Servers
WAISIndex onFull Text
Centralized
X.500Name
ComponentsDistributed
Among Servers
Netfind UsersDistributed
Among Hosts
