1 HEINZ NIXDORF INSTITUT University of Paderborn Algorithms und Complexity Seminar Algorithms of the Internet Christian Schindelhauer 2004-04-19

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HEINZ NIXDORF INSTITUTUniversity of Paderborn

Algorithms und Complexity

SeminarAlgorithms of the Internet

Christian Schindelhauer2004-04-19

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HEINZ NIXDORF INSTITUTEUniversity of Paderborn

Algorithms und ComplexityChristian Schindelhauer

Seminar Algorithms of the Internet

Motivation

• The Internet– is the public global wide-area interconnection network for

computers– grows exponentially– evolves

The evolution of the Internet• Crises and catastrophes

– Computer hackers since the 70s– The traffic breakdown in the 80s– Denial of service attacks in the 90s– SPAM forever

• Clever algorithmic solutions – Secure protocols– TCP bandwidth control– DoS-detection– SPAM-filters

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Goals of the Seminar

• Algorithms of the Internet• Literature recherche in a hot topic• Write an survey on the state of the art• Give a presentation on this field• Interact with others on scientific research• Provide material for

– the community– future lectures and seminars– a book

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Organization

• See the Web-page

http://wwwcs.upb.de/cs/ag-madh/WWW/Teaching/2004SS/AlgInternet/

• Today: RegistrationAssignment of topics

• Next two meetings: Kickoff and feedback• May 10th/17th: 2pm-6pm

1st presentation• From May to July weekly (voluntary) meetings for

consultation• July 19th/26th: 1pm-7pm

2nd presentation• August 1st (11:59 pm): Deadline for written assignment• August 30th (2pm): Evaluation, grades and comments

(voluntary participation)

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The Deliverables

• 1st presentation– Duration 15 min.– Presents

• main issue• strategy to get the work done

• 2nd presentation– Duration 45 min.– Survey of the research area

• Written assignment– 5-10 pages (pure text without title, references, and figures)– Survey of the most relevant and interesting work in the

assigned area

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How it Counts for the Grade

• 1st presentation– 0%

• 2nd presentation– 25 %

• Written assignment– 75 %

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The Topics

1. The mobile Internet2. P2P-networks3. Web caching4. Algorithms for Web search engines5. The structure of the Web6. Security mechanisms of the Internet7. Denial of service attacks8. Worms, viruses and spam9. Epidemic algorithms10. The Domain Name System (DNS)11. Bandwidth allocation of TCP12. Routing algorithms of IP13. Broadcasting and Multicasting in IP14. The self-organization of the Internet15. “Wild card”

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Contents of Written Assignment

• Scientific survey on the assigned topic• For broad audience interested in algorithms and Internet

Table of contents for “Tachyonic Networking”1. What is Tachyonic Network Transmissions (TNT)2. Applications of TNT3. How TNT began4. The main streams of TNT5. Recent developments in Tachyonic Networking and

Computing6. Focus: The TachyNet - A clever solution of TNT7. Open problems and upcoming developments• References

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Format and Layout of Written Assignment

• American English• Neutral style• 5-10 pages (pure text without title, references, and figures)• Accurate and correct citations and references• LATeX, BibTeX• Deliverables

– LATeX source file– BibTeX file– Compiled PDF-output– As many referred text documents as possible

• Electronically if possible• On paper if necessary

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1. The Mobile Internet

• IP Tunneling• Mobile Ad-hoc Networks• Handhelds, PDA• UMTS, WAP

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2. P2P-Networks

• 1st generation– Napster, Kazaa, Gnutella

• Modern P2P-Networks– CAN, CHORD, Tapestry, …

• Visit the lecture “Algorithmen für Peer-to-Peer-Netzwerke”• But do not copy (all)

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3. Web Caching

• Relieving hot spots in the Internet• Akamai• Distributed Hash Tables• Take a look into the script “Algorithmische Grundlagen des

Internets”, Summer 2003

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4. Web Search Engines

• Commercial systems– Google, Alltheweb, Altavista, etc– look at websearchengineshowdown.com

• Algorithmic solutions– PageRank by Brin and Page (Google)– Kleinberg’s HITS-algorithm

• Take a look into the script “Algorithmische Grundlagen des Internets”, Summer 2003 and 2004

• Contact Peter Mahlmann!

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5. The Structure of the Web

• The WWW is made by individuals• Yet the structure can be described by Pareto-distribution

– number of links, size of connected components• The graph structure of the WWW• Take a look into the script “Algorithmische Grundlagen des

Internets”, Summer 2002• Link to Web search machines

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6. Security mechanisms of the Internet

• Are there any?• Is it all trust-based?

• Start your investigations for the search of the missing crypto-layer of TCP/IP at the secure shell protocol

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7. Denial of Service Attacks

• A new problem from the 90s• Solutions

– Ingress filtering– Link testing– Logging– ICMP Trace back– Marking (!!!)

• Take a look into the script “Algorithmische Grundlagen des Internets”, Summer 2003

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8. Worms, Viruses, and SPAM

• Definition• How they spread• How they work• The perfect Antivirus-Software• An Immune-System for Computers

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9. Epidemic Algorithms

• Demers et al.– Epidemic algorithms for mirroring data bases– Idea: Spread information like a virus

• Some analyses and new ideas by– Karp et al. 2001, Randomized Rumor Spreading

• Take a look into the script “Algorithmische Grundlagen des Internets”, Summer 2002

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10. The Domain Name System

• What is it?• How does it work?• Why is it so stable?• Alternatives?

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11. Bandwidth Allocation of TCP

• Very classical problem of TCP/IP• Strangely enough network congestion in the Internet is healed

in the transport layer and not in the network layer• Start with the scripts

– Algorithmische Grundlagen des Internets”, Summer 2002 and 2003

• Random early deletion (RED)• New TCP-allocation for Tera-Baud-connections

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12. Routing Algorithms of IP

• Start with the standard algorithms• There are lots of theoretical work of routing algorithms• Concentrate on such algorithms related to IP

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13. Broadcasting and Multicasting in IP

• IPv4 and IPv6 foresee multicasting• How does it work?• How can it be improved? • Is it possible to have TV on IP?

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14. The self-organization of the Internet

• Official organizations of the Internet (IETF, …)• The Internet and its self-regulation

– socially and technology based

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15. “Wild Card”

• Did we miss something?• Take a hot topic of your choice within this area.

• If everything fails, I’ll help.

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HEINZ NIXDORF INSTITUTUniversity of Paderborn

Algorithms und Complexity

Thanks and let’s go!Thanks and let’s go!

Verteilte Algorithmen in Netzwerken

Christian Schindelhauer

Documents

1 HEINZ NIXDORF INSTITUT University of Paderborn Algorithms und Complexity Seminar Algorithms of the Internet Christian Schindelhauer 2004-04-19