PPT-Peer to Peer Networks Distributed Hash Tables

Distributed Hash Tables Chord Kelips Dynamo Galen Marchetti Cornell University 1960s 1999 Research Origins ARPANET every node requests and serves content No selforganization USENET. In Section 4 of this Appendix the tables are carried out to a large number of decimal places and exact values are indicated by underlining In most of the other tables only a limited number of decimal places are given therefore making the tables bett Spencer Dawson. Summary. What are rainbow tables?. A time and memory tradeoff in password cracking.. A piecewise approach to one-way hashes. What are the advantages/disadvantages. Best uses. Limitations. Motivating Applications. Large collection of datasets. Datasets are dynamic (insert, delete). Goal: efficient searching/insertion/deletion. Hashing is ONLY applicable for exact-match searching. Direct Address Tables. Case Study: Amazon Dynamo. Steve Ko. Computer Sciences and Engineering. University at Buffalo. Recap. CAP Theorem?. Consistency, Availability, Partition Tolerance. Pick two. Eventual consistency?. Availability and partition tolerance over consistency. Linear Probing. Uri Zwick. Tel Aviv University. Hashing with open addressing. “Uniform probing”. Insert key . in the first free position among.  . (Sometimes) assumed to be a . permutation. To search, follow the same order. CIS 606. Spring 2010. Hash tables. Many applications require a dynamic set that supports only the . dictionary . operations . INSERT. , SEARCH, and DELETE. Example: a symbol table in a compiler.. A hash table is effective for implementing a dictionary.. Plan. I spent the last decade advising on numerous cases where hash tables/functions were used. A few observations on . What data structures I’ve seen implemented and where. What do developers think, were they need help. Introduction. What is a Peer-To-Peer Network. A Peer. Application Overlay Network. Network Architecture and System Types. Advantages and Disadvantages. Bittorrent. Protocol. Conclusion. What is it?. We have:. Discussed techniques for hashing. Discussed mapping down to a given range . 0, ..., . M. – 1. Now we must deal with collisions. Numerous techniques exist. Containers in general. Specifically linked lists. Hash Tables. . . 0. 1. 2. 3. 4. 451-229-0004. 981-101-0002. 025-612-0001. © 2014 Goodrich, Tamassia, Godlwasser. Presentation for use with the textbook . Data Structures and Algorithms in Java, 6. COS . 518. : . Advanced Computer Systems. Lecture . 15. Daniel Suo. [Credit: . All slides copied wholesale from Kyle Jamieson and . Mike Freedman.. Selected . content adapted from B. Karp, R. Morris]. COS 518: . Advanced Computer Systems. Lecture 16. Michael Freedman. [Credit: Slides Adapted from Kyle Jamieson and Daniel . Suo. ]. Peer-to-Peer Systems. Napster, Gnutella, BitTorrent, challenges. Distributed Hash Tables. CSE 373: Data Structures and Algorithms. Thanks to Kasey Champion, Ben Jones, Adam Blank, Michael Lee, Evan McCarty, Robbie Weber, Whitaker Brand, Zora Fung, Stuart . Reges. , Justin Hsia, Ruth Anderson, and many others for sample slides and materials .... A common approach is to use a . Distributed Hash Table. (DHT). to organize . nodes. Traditional . hash functions convert a key to a hash value, which can be used as an index into a hash table.. Keys are unique.