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Distributed Web Crawling
Distributed web crawling is a distributed computing technique whereby Internet search engines employ many computers to index the Internet via web crawling. Such systems may allow for users to voluntarily offer their own computing and bandwidth resources towards crawling web pages. By spreading the load of these tasks across many computers, costs that would otherwise be spent on maintaining large computing clusters are avoided. Types Cho and Garcia-Molina studied two types of policies: Dynamic assignment With this type of policy, a central server assigns new URLs to different crawlers dynamically. This allows the central server to, for instance, dynamically balance the load of each crawler. With dynamic assignment, typically the systems can also add or remove downloader processes. The central server may become the bottleneck, so most of the workload must be transferred to the distributed crawling processes for large crawls. There are two configurations of crawling architectures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Computing
A distributed system is a system whose components are located on different computer network, networked computers, which communicate and coordinate their actions by message passing, passing messages to one another from any system. Distributed computing is a field of computer science that studies distributed systems. The components of a distributed system interact with one another in order to achieve a common goal. Three significant challenges of distributed systems are: maintaining concurrency of components, overcoming the clock synchronization, lack of a global clock, and managing the independent failure of components. When a component of one system fails, the entire system does not fail. Examples of distributed systems vary from service-oriented architecture, SOA-based systems to massively multiplayer online games to peer-to-peer, peer-to-peer applications. A computer program that runs within a distributed system is called a distributed program, and ''distributed programming' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fandom (website)
Fandom (formerly known as Wikicities before 2007 and later Wikia before 2019) is a wiki hosting service that hosts wikis mainly on entertainment topics (i.e. video games, TV series, movies, entertainers, etc.). Its domain is operated by Fandom, Inc. (formerly known as Wikia, Inc. until 2019), a for-profit Delaware company founded in October 2004 by Jimmy Wales (co-founder of Wikipedia) and Angela Beesley. Fandom was acquired in 2018 by TPG Capital and Jon Miller through Integrated Media Co. Fandom uses MediaWiki, the open-source wiki software used by Wikipedia. Fandom, Inc. derives its income from advertising and sold content, publishing most user-provided text under copyleft licenses. The company also runs the associated Fandom editorial project, offering pop-culture and gaming news. Fandom wikis are hosted under the domain ''fandom.com'', but some, especially those that focus on subjects other than media franchises, were hosted under ''wikia.org'' until November 2021. Hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seeks
Seeks is a free and open-source project licensed under the GNU Affero General Public License version 3 (AGPL-3.0-or-later). It exists to create an alternative to the current market-leading search engines, driven by user concerns rather than corporate interests. The original manifesto was created by Emmanuel Benazera and Sylvio Drouin and published in October 2006. The project was under active development until April 2014, with both stable releases of the engine and revisions of the source code available for public use. In September 2011, Seeks won an innovation award at the Open World Forum Innovation Awards. The Seeks source code has not been updated since April 28, 2014 and no Seeks nodes have been usable since February 6, 2016. User control Seeks aims to give the control of the ranking of results to the users, as search algorithms are often less accurate than humans. It relies on a distributed collaborative filter to let users personalize and share their preferred result ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YaCy
''YaCy'' (pronounced “ya see”) is a free distributed search engine, built on the principles of peer-to-peer (P2P) networks created by Michael Christen in 2003. The engine is written in Java and distributed on several hundred computers, , so-called YaCy-peers. Each YaCy-peer independently crawls through the Internet, analyzes and indexes found web pages, and stores indexing results in a common database (so-called index) which is shared with other YaCy-peers using principles of peer-to-peer. It is a search engine that everyone can use to build a search portal for their intranet and to help search the public internet clearly. Compared to semi-distributed search engines, the YaCy-network has a distributed architecture. All YaCy-peers are equal and no central server exists. It can be run either in a crawling mode or as a local proxy server, indexing web pages visited by the person running YaCy on their computer. Several mechanisms are provided to protect the user's privacy. Acces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Web Crawler
A Web crawler, sometimes called a spider or spiderbot and often shortened to crawler, is an Internet bot that systematically browses the World Wide Web and that is typically operated by search engines for the purpose of Web indexing (''web spidering''). Web search engines and some other websites use Web crawling or spidering software to update their web content or indices of other sites' web content. Web crawlers copy pages for processing by a search engine, which indexes the downloaded pages so that users can search more efficiently. Crawlers consume resources on visited systems and often visit sites unprompted. Issues of schedule, load, and "politeness" come into play when large collections of pages are accessed. Mechanisms exist for public sites not wishing to be crawled to make this known to the crawling agent. For example, including a robots.txt file can request bots to index only parts of a website, or nothing at all. The number of Internet pages is extremely large; ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Computing
A distributed system is a system whose components are located on different computer network, networked computers, which communicate and coordinate their actions by message passing, passing messages to one another from any system. Distributed computing is a field of computer science that studies distributed systems. The components of a distributed system interact with one another in order to achieve a common goal. Three significant challenges of distributed systems are: maintaining concurrency of components, overcoming the clock synchronization, lack of a global clock, and managing the independent failure of components. When a component of one system fails, the entire system does not fail. Examples of distributed systems vary from service-oriented architecture, SOA-based systems to massively multiplayer online games to peer-to-peer, peer-to-peer applications. A computer program that runs within a distributed system is called a distributed program, and ''distributed programming' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nutch
Apache Nutch is a highly extensible and scalable open source web crawler software project. Features Nutch is coded entirely in the Java programming language, but data is written in language-independent formats. It has a highly modular architecture, allowing developers to create plug-ins for media-type parsing, data retrieval, querying and clustering. The fetcher ("robot" or "web crawler") has been written from scratch specifically for this project. History Nutch originated with Doug Cutting, creator of both Lucene and Hadoop, and Mike Cafarella. In June, 2003, a successful 100-million-page demonstration system was developed. To meet the multi-machine processing needs of the crawl and index tasks, the Nutch project has also implemented a MapReduce facility and a distributed file system. The two facilities have been spun out into their own subproject, called Hadoop. In January, 2005, Nutch joined the Apache Incubator, from which it graduated to become a subproject of Lucen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
URLs
A Uniform Resource Locator (URL), colloquially termed as a web address, is a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it. A URL is a specific type of Uniform Resource Identifier (URI), although many people use the two terms interchangeably. URLs occur most commonly to reference web pages (HTTP) but are also used for file transfer (FTP), email (mailto), database access (JDBC), and many other applications. Most web browsers display the URL of a web page above the page in an address bar. A typical URL could have the form http://www.example.com/index.html, which indicates a protocol (http), a hostname (www.example.com), and a file name (index.html). History Uniform Resource Locators were defined in in 1994 by Tim Berners-Lee, the inventor of the World Wide Web, and the URI working group of the Internet Engineering Task Force (IETF), as an outcome of collaboration started at the IETF Living Documents birds of a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grub (search Engine)
Grub is an open source distributed search crawler platform. Users of Grub could download the peer-to-peer grubclient software and let it run during their computer's idle time. The client indexed the URLs and sent them back to the main grub server in a highly compressed form. The collective crawl could then, in theory, be utilized by an indexing system, such as the one being proposed at Wikia Search. Grub was able to quickly build a large snapshot by asking thousands of clients to crawl and analyze a small portion of the web each. Wikia has now released the entire Grub package under an open source software license. However, the old Grub clients are not functional anymore. New clients can be found on the Wikia wiki. History The project was started in 2000 by Kord Campbell, Igor Stojanovski, and Ledio Ago in Oklahoma City. Intellectual property rights were acquired from Grub in January 2003 for $1.3 million in cash and stock by LookSmart. For a short time the original team c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet
The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and file sharing. The origins of the Internet date back to the development of packet switching and research commissioned by the United States Department of Defense in the 1960s to enable time-sharing of computers. The primary precursor network, the ARPANET, initially served as a backbone for interconnection of regional academic and military networks in the 1970s to enable resource shari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LookSmart
LookSmart is an American search advertising, content management, online media, and technology company. It provides search, machine learning and chatbot technologies as well as pay-per-click and contextual advertising services. LookSmart also licenses and manages search ad networks as white-label products. It abides by the click measurement guidelines of the Interactive Advertising Bureau. LookSmart also owns several subsidiaries, including Clickable Inc., LookSmart AdCenter, Novatech.io, ShopWiki and Syncapse. The current CEO of LookSmart is Michael Onghai and the company is headquartered in Henderson, Nevada. Etymology The name "LookSmart" is a double entendre, referring to both its selective, editorially compiled directory and as a compliment to users whom the company thinks "look smart". History 1995–1998 LookSmart was founded as Homebase in 1995 in Melbourne, Australia by husband and wife Evan Thornley and Tracy Ellery, executives of McKinsey & Company. Reader's Di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yahoo
Yahoo! (, styled yahoo''!'' in its logo) is an American web services provider. It is headquartered in Sunnyvale, California and operated by the namesake company Yahoo! Inc. (2017–present), Yahoo Inc., which is 90% owned by investment funds managed by Apollo Global Management and 10% by Verizon Communications. It provides a web portal, search engine Yahoo! Search, Yahoo Search, and related services, including My Yahoo!, Yahoo! Mail, Yahoo Mail, Yahoo! News, Yahoo News, Yahoo! Finance, Yahoo Finance, Yahoo! Sports, Yahoo Sports and its advertising platform, Yahoo! Native. Yahoo was established by Jerry Yang and David Filo in January 1994 and was one of the pioneers of the early Internet era in the 1990s. However, usage declined in the late 2000s as some services discontinued and it lost market share to Facebook and Google. History Founding In January 1994, Yang and Filo were electrical engineering graduate students at Stanford University, when they created a website named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
