PPT-Peer-to-Peer Systems and Distributed Hash Tables

COS 418 Distributed Systems Lecture 7 Kyle Jamieson Credit Selected content adapted from B Karp R Morris PeertoPeer Systems Napster Gnutella BitTorrent challenges Distributed Hash Tables. Chord and Dynamo. Costin Raiciu,. Advanced Topics in Distributed Systems. 18/12/2012. Motivation: file sharing. Many users want to share files online. If a file’s location is known, downloading is easy. Lecture 3. Sets. A . set. is simply a collection of elements. Unlike lists, elements are not ordered. Very abstract, general concept with broad usefulness:. The set of all Google search queries from the past 24 hours. 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. 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. Passwords stored in computers are changed from their plain text form to an encrypted value.. These values are called hashes, and there is a unique plain text value for every hash.. A rainbow table is a lookup table offering a time-memory tradeoff used in recovering the plaintext password from a password hash generated by a hash function . Sig Freund. CSC 8320 Fall . 2008. rfreund1@student.gsu.edu. Transparency in Distributed Operating Systems. Evolution of Modern Operating Systems. Centralized operating system. +network access and resource sharing. . Sections 5.3, 5.4, 5.5, 5.6. 2. Designing a Hash Table. Hash function: establishing a key with an indexed location in a hash table.. E.g. . Index = hash(key) % table_size;. Resolve conflicts: . Need to handle case where multiple keys mapped to the same index.. 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 16. Michael Freedman. [Credit: Slides Adapted from Kyle Jamieson and Daniel . Suo. ]. Peer-to-Peer Systems. Napster, Gnutella, BitTorrent, challenges. Distributed Hash Tables. Distributed Computing CSC 345 – Operating Systems By - Fure Unukpo 1 Saturday, April 26, 2014 Outline Introduction Design and Architecture Client–server Three-tier Client–server Architecture Instructor: Lilian de Greef Quarter: Summer 2017 CSE 373: Data Structures and Algorithms Lecture 6: Finishing Amortized Analysis; Dictionaries ADT; Introduction to Hash Tables Today: Finish up Amortized Analysis Lecture . 19 . – . BigTable. , Spanner. , . Hashing. Overview. BigTable. Spanner. Hashing Tricks. 2. BigTable. Distributed storage system for managing structured data.. Designed to scale to a very large size. Dr. . Barsha. . Mitra. CSIS . Dept. , BITS Pilani, Hyderabad Campus. Introduction. Course ID: SS ZG526, Title: Distributed Computing. allows for flexibly sharing resources (e.g., files and multimedia documents) stored across network-wide computers.