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80legs
80legs is a web crawling service that allows its users to create and run web crawls through its software as a service platform. History 80legs was created by Computational Crawling, a company in Houston, Texas. The company launched the private beta of 80legs in April 2009 and publicly launched the service at the DEMOfall 09 conference. At the time of its public launch, 80legs offered customized web crawling and scraping services. It has since added subscription plans and other product offerings. Technology 80legs is built on top of a distributed grid computing network. This grid consists of approximately 50,000 individual computers, distributed across the world, and uses bandwidth monitoring technology to prevent bandwidth cap overages. 80legs has been criticised by numerous site owners for its technology effectively acting as a Distributed Denial of Service attack and not obeying robots.txt. As the average webmaster is not aware of the existence of 80legs, blocking access ...
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Web Crawling
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; even ...
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Software As A Service
Software as a service (SaaS ) is a software licensing and delivery model in which software is licensed on a subscription basis and is centrally hosted. SaaS is also known as "on-demand software" and Web-based/Web-hosted software. SaaS is considered to be part of cloud computing, along with infrastructure as a service (IaaS), platform as a service (PaaS), desktop as a service (DaaS), managed software as a service (MSaaS), mobile backend as a service (MBaaS), data center as a service (DCaaS), integration platform as a service (iPaaS), and information technology management as a service (ITMaaS). SaaS apps are typically accessed by users of a web browser (a thin client). SaaS became a common delivery model for many business applications, including office software, messaging software, payroll processing software, DBMS software, management software, CAD software, development software, gamification, virtualization, accounting, collaboration, customer relationship management (CR ...
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Houston, Texas
Houston (; ) is the most populous city in Texas, the most populous city in the Southern United States, the fourth-most populous city in the United States, and the sixth-most populous city in North America, with a population of 2,304,580 in 2020. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the seat and largest city of Harris County and the principal city of the Greater Houston metropolitan area, which is the fifth-most populous metropolitan statistical area in the United States and the second-most populous in Texas after Dallas–Fort Worth. Houston is the southeast anchor of the greater megaregion known as the Texas Triangle. Comprising a land area of , Houston is the ninth-most expansive city in the United States (including consolidated city-counties). It is the largest city in the United States by total area whose government is not consolidated with a county, parish, or borough. Though primarily in Harris County, small portions of the ...
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Grid Computing
Grid computing is the use of widely distributed computer resources to reach a common goal. A computing grid can be thought of as a distributed system with non-interactive workloads that involve many files. Grid computing is distinguished from conventional high-performance computing systems such as cluster computing in that grid computers have each node set to perform a different task/application. Grid computers also tend to be more heterogeneous and geographically dispersed (thus not physically coupled) than cluster computers. Although a single grid can be dedicated to a particular application, commonly a grid is used for a variety of purposes. Grids are often constructed with general-purpose grid middleware software libraries. Grid sizes can be quite large. Grids are a form of distributed computing composed of many networked loosely coupled computers acting together to perform large tasks. For certain applications, distributed or grid computing can be seen as a special type of ...
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Distributed Denial Of Service
In computing, a denial-of-service attack (DoS attack) is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Denial of service is typically accomplished by flooding the targeted machine or resource with superfluous requests in an attempt to overload systems and prevent some or all legitimate requests from being fulfilled. In a distributed denial-of-service attack (DDoS attack), the incoming traffic flooding the victim originates from many different sources. More sophisticated strategies are required to mitigate this type of attack, as simply attempting to block a single source is insufficient because there are multiple sources. A DoS or DDoS attack is analogous to a group of people crowding the entry door of a shop, making it hard for legitimate customers to enter, thus disrupting trade. Criminal perpetrators of DoS attacks oft ...
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Robots Exclusion Standard
The robots exclusion standard, also known as the robots exclusion protocol or simply robots.txt, is a standard used by websites to indicate to visiting web crawlers and other web robots which portions of the site they are allowed to visit. This relies on voluntary compliance. Not all robots comply with the standard; email harvesters, spambots, malware and robots that scan for security vulnerabilities may even start with the portions of the website where they have been told to stay out. The "robots.txt" file can be used in conjunction with sitemaps, another robot inclusion standard for websites. History The standard was proposed by Martijn Koster, when working for Nexor in February 1994 on the ''www-talk'' mailing list, the main communication channel for WWW-related activities at the time. Charles Stross claims to have provoked Koster to suggest robots.txt, after he wrote a badly-behaved web crawler that inadvertently caused a denial-of-service attack on Koster's server. I ...
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OpenStreetMap
OpenStreetMap (OSM) is a free, open geographic database updated and maintained by a community of volunteers via open collaboration. Contributors collect data from surveys, trace from aerial imagery and also import from other freely licensed geodata sources. OpenStreetMap is freely licensed under the Open Database License and as a result commonly used to make electronic maps, inform turn-by-turn navigation, assist in humanitarian aid and data visualisation. OpenStreetMap uses its own topology to store geographical features which can then be exported into other GIS file formats. The OpenStreetMap website itself is an online map, geodata search engine and editor. In 2004, OpenStreetMap was created by Steve Coast in response to the Ordnance Survey, the United Kingdom's national mapping agency, failing to release its data to the public and under free licences. Initially, maps were created only via GPS traces, but it was quickly populated by importing public domain geographical ...
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Modsecurity
ModSecurity, sometimes called Modsec, is an open-source web application firewall (WAF). Originally designed as a module for the Apache HTTP Server, it has evolved to provide an array of Hypertext Transfer Protocol request and response filtering capabilities along with other security features across a number of different platforms including Apache HTTP Server, Microsoft IIS and Nginx. It is a free software released under the Apache license 2.0. The platform provides a rule configuration language known as 'SecRules' for real-time monitoring, logging, and filtering of Hypertext Transfer Protocol communications based on user-defined rules. Although not its only configuration, ModSecurity is most commonly deployed to provide protections against generic classes of vulnerabilities using the OWASP ModSecurity Core Rule Set (CRS). This is an open-source set of rules written in ModSecurity's SecRules language. The project is part of OWASP, the Open Web Application Security Project. ...
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UserAgent
In computing, a user agent is any software, acting on behalf of a user, which "retrieves, renders and facilitates end-user interaction with Web content". A user agent is therefore a special kind of software agent. Some prominent examples of user agents are web browsers and email readers. Often, a user agent acts as the client in a client–server system. In some contexts, such as within the Session Initiation Protocol (SIP), the term ''user agent'' refers to both end points of a communications session. User agent identification When a software agent operates in a network protocol, it often identifies itself, its application type, operating system, device model, software vendor, or software revision, by submitting a characteristic identification string to its operating peer. In HTTP, SIP,RFC 3261, ''SIP: Session Initiation Protocol'', IETF, The Internet Society (2002) and NNTP protocols, this identification is transmitted in a header field ''User-Agent''. Bots, such as Web cra ...
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Wrecksite
Wrecksite is a non-profit organization that documents maritime wrecks around the world and is free to use. Accessing more data requires a subscription. The website is the world largest online nautical wreck database, and has 187,030 wrecks and 164,050 positions, 62,730 images, 2,347 maritime charts, 31,070 ship owners and builders. () Bibliography Notes References * * * - Total pages: 217 * Internet properties established in 2001 Online databases {{Digital-library-stub ...
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